{{Short description|Web browser content blocking extension}} {{Use mdy dates|date=September 2020}} {{Use American English|date=January 2022}} {{Lowercase title}} {{Infobox software | name = uBlock Origin | logo = UBlock_Origin.svg | logo_alt = uBlock Origin logo, consisting of the text "uo" on a shield. | logo_size = 70px | screenshot = Screenshot of the uBlock Origin UI on Firefox.png | screenshot_alt = uBlock Origin pop-up interface as of version 1.27.6 | screenshot_size = 210px | caption = uBlock Origin pop-up interface | author = Raymond Hill (gorhill) | developer = '''Current:'''<br />Raymond Hill<br />'''Past:''' <br />Deathamns, Chris Aljoudi, Alex Vallat<ref name="Contributors">{{cite web |url=https://github.com/gorhill/uBlock/graphs/contributors |title=Contributors to gorhill/uBlock |work=GitHub |access-date=December 4, 2019 |archive-date=December 14, 2019 |archive-url=https://web.archive.org/web/20191214072224/https://github.com/gorhill/uBlock/graphs/contributors |url-status=live }}</ref> | released = {{Start date and age|2014|06|23}}<ref>{{cite web |url=https://github.com/gorhill/uBlock/wiki/Change-log#0100 |title=Changelog for the first versions |website=GitHub |access-date=December 4, 2019 |archive-date=December 23, 2019 |archive-url=https://web.archive.org/web/20191223212603/https://github.com/gorhill/uBlock/wiki/Change-log#0100 |url-status=live }}</ref> | latest release version = {{wikidata|property|reference|P348}} | latest release date = {{start date and age|{{wikidata|qualifier|P348|P577}}}} | programming language = JavaScript | operating system = Cross-platform | replaces = HTTP Switchboard and uMatrix | language count = 72<ref>{{cite web |url=https://crowdin.com/project/ublock |title=Completed translations |website=Crowdin.com |access-date=May 16, 2024 |archive-date=October 29, 2019 |archive-url=https://web.archive.org/web/20191029190309/https://crowdin.com/project/ublock |url-status=live }}</ref> | genre = Browser extension | license = GPLv3 }} '''uBlock Origin''' ({{IPAc-en|ˈ|j|uː|b|l|ɒ|k}} {{Respell|YOO|blok}}<ref>{{Cite web |title=uBlock Origin: README.md |url=https://github.com/gorhill/uBlock/blob/master/README.md |website=uBlock GitHub Repository |date=December 25, 2022 |via=GitHub |quote=pronounced you-block origin (/ˈjuːˌblɒk/) |access-date=August 23, 2015 |archive-date=January 31, 2022 |archive-url=https://web.archive.org/web/20220131120305/https://github.com/gorhill/uBlock/blob/master/README.md |url-status=live }}</ref>) is a free and open-source browser extension for content filtering, including ad blocking. The extension is available for Firefox and Chromium-based browsers (such as Chrome, Edge, Brave, and Opera).<ref name="gorhill_readme">{{cite web |title=uBlock / README.md |url=https://github.com/gorhill/uBlock/blob/master/README.md |access-date=December 4, 2019 |website=GitHub |archive-date=January 31, 2022 |archive-url=https://web.archive.org/web/20220131120305/https://github.com/gorhill/uBlock/blob/master/README.md |url-status=live }}</ref>

uBlock Origin is actively developed and maintained by its creator and lead developer Raymond Hill and the open source community.<ref name="Contributors" /> {{As of|2025|12}}, the Chrome version of uBlock Origin had over 29 million active users and the Firefox version has over 10 million active users, making it the most popular extension on Firefox.<ref>{{cite web |title=uBlock Origin Chrome |url=https://chrome.google.com/webstore/detail/ublock-origin/cjpalhdlnbpafiamejdnhcphjbkeiagm |access-date=2025-04-27 |website=chrome.google.com |archive-date=February 5, 2021 |archive-url=https://web.archive.org/web/20210205025700/https://chrome.google.com/webstore/detail/ublock-origin/cjpalhdlnbpafiamejdnhcphjbkeiagm |url-status=live }}</ref><ref>{{Cite web |url=https://addons.mozilla.org/en-US/firefox/search/?sort=users&amp;type=extension |title=Search results for Firefox Browser add-ons |website=Firefox Browser Add-ons |publisher=Mozilla Foundation |access-date=2025-04-27}}</ref>

==History== The development of uBlock Origin (uBO) came about by forking the codebase of HTTP Switchboard, an extension designed to give users control over browser requests. uBlock, which was the predecessor of uBlock Origin, was further influenced by uMatrix, another browser extension created by forking HTTP Switchboard.<ref name="uMatrix">{{cite web |title=uMatrix |url=https://github.com/gorhill/uMatrix |access-date=December 4, 2019 |website=GitHub |archive-date=January 31, 2022 |archive-url=https://web.archive.org/web/20220131120155/https://github.com/gorhill/uMatrix |url-status=live }}</ref>

=== HTTP Switchboard === HTTP Switchboard was initially released on September 20, 2013.<ref>{{cite web |title=History for icon_128.png - gorhill/httpswitchboard |url=https://github.com/gorhill/httpswitchboard/commits/master/icon_128.png |access-date=17 December 2024 |website=GitHub |language=en |archive-date=August 18, 2025 |archive-url=https://web.archive.org/web/20250818033012/https://github.com/gorhill/httpswitchboard/commits/master/icon_128.png |url-status=live }}</ref><ref name="gorhill/httpswitchboard/FAQ">{{cite web |author1=gorhill |title=FAQ |url=https://github.com/gorhill/httpswitchboard/wiki/FAQ |access-date=17 December 2024 |website=httpswitchboard |publisher=GitHub |language=en |archive-date=December 19, 2024 |archive-url=https://web.archive.org/web/20241219102311/https://github.com/gorhill/httpswitchboard/wiki/FAQ |url-status=live }}</ref><ref>{{cite web |author1=gorhill |title=HTTP Switchboard 1.0.0.2 · |url=https://github.com/gorhill/httpswitchboard/releases/tag/1.0.0.2 |website=Release |publisher=GitHub |language=en |access-date=December 17, 2024 |archive-date=August 19, 2025 |archive-url=https://web.archive.org/web/20250819171442/https://github.com/gorhill/httpswitchboard/releases/tag/1.0.0.2 |url-status=live }}</ref><ref>* [https://www.grc.com/sn/sn-523.pdf sn-523: uBlock Origin] {{Webarchive|url=https://web.archive.org/web/20241221020015/https://www.grc.com/sn/sn-523.pdf |date=December 21, 2024 }} - Gibson Research * [https://www.grc.com/sn/sn-523-notes.pdf Security Now! #523 notes - 09-01-15 uBlock Origin] {{Webarchive|url=https://web.archive.org/web/20241221020020/https://www.grc.com/sn/sn-523-notes.pdf |date=December 21, 2024 }} - Gibson Research</ref><ref name="github/gorhill/sessbench">{{cite web |last1=Hill |first1=Raymond |date=9 December 2024 |title=Browser session benchmarker |url=https://github.com/gorhill/sessbench |access-date=17 December 2024 |website=sessbench |publisher=gorhill/github |archive-date=August 17, 2025 |archive-url=https://web.archive.org/web/20250817033507/https://github.com/gorhill/sessbench |url-status=live }}</ref><ref name="ghacks/ublock-http-switchboard">{{cite news |last1=Brinkmann |first1=Martin |date=24 June 2014 |title=uBlock for Chrome is a resource-friendly adblocker by the HTTP Switchboard author - gHacks Tech News |url=https://www.ghacks.net/2014/06/24/ublock-chrome-resource-friendly-adblocker-http-switchboard-author/ |access-date=17 December 2024 |work=gHacks |archive-date=March 24, 2020 |archive-url=https://web.archive.org/web/20200324085337/https://www.ghacks.net/2014/06/24/ublock-chrome-resource-friendly-adblocker-http-switchboard-author/ |url-status=live }}</ref> It enabled users to control the types of requests made by their browser, providing a way to block specific types of web content. However, development of HTTP Switchboard ceased on May 18, 2015.<ref name="gorhill/uMatrix/wiki">{{cite web |title=Home |url=https://github.com/gorhill/uMatrix/wiki |access-date=17 December 2024 |website=uMatrix wiki |publisher=GitHub |language=en |archive-date=July 13, 2025 |archive-url=https://web.archive.org/web/20250713012444/https://github.com/gorhill/uMatrix/wiki |url-status=live }}</ref><ref>{{cite web |title=Adblock Plus is probably the reason Firefox and Chrome are such memory hogs |url=https://news.ycombinator.com/item?id=8802424 |access-date=17 December 2024 |website=news.ycombinator.com {{!}} Hacker News |language=en |archive-date=September 14, 2024 |archive-url=https://web.archive.org/web/20240914142712/https://news.ycombinator.com/item?id=8802424 |url-status=live }}</ref>

=== uMatrix === Following the end of HTTP Switchboard's development, uMatrix was introduced on October 24, 2014.<ref>{{cite web |author1=Raymond Hill (gorhill) |title=uMatrix |url=https://chromewebstore.google.com/detail/umatrix/ogfcmafjalglgifnmanfmnieipoejdcf |access-date=17 December 2024 |website=chromewebstore.google.com - Chrome Web Store |archive-date=August 17, 2025 |archive-url=https://web.archive.org/web/20250817235640/https://chromewebstore.google.com/detail/umatrix/ogfcmafjalglgifnmanfmnieipoejdcf |url-status=live }}</ref><ref name="uMatrix"/><ref>{{cite web |title=uMatrix – Extension for Firefox |url=https://addons.mozilla.org/firefox/addon/umatrix/ |access-date=17 December 2024 |website=addons.mozilla.org}}</ref>

This extension, designed for advanced users, acted as a request firewall, allowing users to control browser requests across two main dimensions: the domains and subdomains to which requests were sent, and the types of requests (such as cookies, images, XMLHttpRequest, frames, and scripts). uMatrix retained much of the user interface from HTTP Switchboard, but significantly expanded its functionality, offering a more granular level of control over web requests.

The evolution of these extensions laid the foundation for uBlock, combining elements from both HTTP Switchboard and uMatrix while streamlining the user experience for broader accessibility.

Development of uMatrix continued for several years alongside development of uBlock Origin, with uMatrix being posed as a blocking option that was "definitely for advanced users".

In a public discussion on 2 August 2020, lead developer Raymond Hill stated that he lacked time to work on uMatrix because it was "a project large enough that [he] would be able to work on it only if [he] wasn't working on uBO." In response to a further comment, Hill stated he would never pass development to anyone after past experience, giving concerns such as monetisation and feature bloat, and he would instead "at most" archive it, offering others the chance to fork the project.<ref>{{cite web |author = Raymond Hill (gorhill) |date = August 2, 2020 |title = Request for a stable uMatrix release (for CNAME uncloaking) |url = https://reddit.com/r/uBlockOrigin/comments/i240ds/request_for_a_stable_umatrix_release_for_cname/g048wyk/ |website = Reddit |access-date = May 4, 2025 |archive-date = May 28, 2023 |archive-url = https://web.archive.org/web/20230528191755/https://www.reddit.com/r/uBlockOrigin/comments/i240ds/request_for_a_stable_umatrix_release_for_cname/g048wyk/ |url-status = live }}</ref>

Development of uMatrix ended on July 21, 2021, without announcement, with the project's GitHub repository being converted to a public archive.

===uBlock===

uBlock<ref group="note">uBlock was initially named "μBlock", but it was later renamed to "uBlock" so as to avoid confusion with how the Greek letter μ (Mu/Micro) should be pronounced.{{citation needed|date=December 2023}}</ref> was developed by Raymond Hill to use community-maintained block lists,<ref name="brinkmann_chrome"> {{cite web | last = Brinkmann | first = Martin | title = uBlock for Chrome is a resource-friendly adblocker by the HTTP Switchboard author | work = gHacks Technology News | url = https://www.ghacks.net/2014/06/24/ublock-chrome-resource-friendly-adblocker-http-switchboard-author/ | date = 2014-06-24 | publisher = Ghacks | access-date = 2025-02-22 | url-status = live | archive-url = https://web.archive.org/web/20250221080214/https://www.ghacks.net/2014/06/24/ublock-chrome-resource-friendly-adblocker-http-switchboard-author/ | archive-date = 2025-02-21 }}</ref> while adding features and raising the code quality to release standards.<ref>{{cite web | first = Raymond | last = Hill | title = Changes from HTTP Switchboard | url = https://github.com/gorhill/uMatrix/wiki/Changes-from-HTTP-Switchboard | date = 2018-06-04 | website = GitHub | access-date = 2025-02-22 | url-status = live | archive-url = https://web.archive.org/web/20250131033318/https://github.com/gorhill/uMatrix/wiki/Changes-from-HTTP-Switchboard | archive-date = 2025-01-31 }}</ref> First released in June 2014 as a Chrome and Opera extension, in 2015 the extension became available in other browsers.{{citation needed|date=December 2023}}

A joint Sourcepoint and comScore survey reported an 833% growth from November 2014 to August 2015, the strongest growth among adblockers listed.<ref>{{cite web |last1 = Levine |first1 = Barry |title = The Ad Blocker Landscape: What You Need To Know Today |url = http://marketingland.com/heres-a-briefer-about-the-top-ad-blockers-146686 |website = Marketing Land |date = October 14, 2015 |access-date = October 17, 2015 |archive-date = February 26, 2021 |archive-url = https://web.archive.org/web/20210226190826/https://marketingland.com/heres-a-briefer-about-the-top-ad-blockers-146686 |url-status = live }}</ref> The report attributed the growth to the desire of users for pure blockers, outside the "acceptable ads" program operated by Adblock Plus.<ref>{{cite web |title = The state of ad blocking - September 2015 |date = September 16, 2015 |url = http://www.slideshare.net/sourcepoint/the-state-of-ad-blocking-september-2015? |publisher = Sourcepoint and comScore |access-date = October 17, 2015 |archive-date = September 29, 2015 |archive-url = https://web.archive.org/web/20150929180717/http://www.slideshare.net/sourcepoint/the-state-of-ad-blocking-september-2015 |url-status = live }}</ref>

The development of uBlock stopped in August 2015 after its April break with uBlock Origin but there were updates again starting in January 2017.<ref>{{cite web |title=uBlockAdmin/uBlock |url=https://github.com/uBlockAdmin/uBlock/commits/ |access-date=December 4, 2019 |website=github.com}}</ref>

In July 2018, ublock.org was acquired by AdBlock and they resumed development.<ref>{{cite news | url = https://www.ublock.org/announcement/ | title = An update on uBlock | date = July 13, 2018 | work = ublock.org | access-date = December 4, 2019 | url-status = dead | archive-url = https://web.archive.org/web/20180719224133/https://www.ublock.org/announcement/ | archive-date = July 19, 2018 }}</ref> From February 2019, uBlock began allowing users to participate in "acceptable ads",<ref>{{cite web | url = https://ublock.org/blog/ublock-incorporates-acceptable-ads/ | title = uBlock Incorporates Acceptable Ads | date = February 23, 2019 | access-date = December 4, 2019 | archive-date = November 30, 2019 | archive-url = https://web.archive.org/web/20191130155329/https://ublock.org/blog/ublock-incorporates-acceptable-ads/ | url-status = dead }}</ref><ref>{{cite web |title = uBlock 0.9.5.13 |url = https://github.com/uBlock-LLC/uBlock/releases/tag/0.9.5.13 |website = GitHub |date = February 13, 2019 |access-date = June 26, 2020 |archive-date = August 16, 2025 |archive-url = https://web.archive.org/web/20250816232427/https://github.com/uBlock-LLC/uBlock/releases/tag/0.9.5.13 |url-status = live }}</ref> a program run by Adblock Plus that allows some ads deemed "acceptable" and nonintrusive, and for which larger publishers pay a fee.<ref>{{cite web | title = About Adblock Plus | url = https://adblockplus.org/en/about | website = adblockplus.org | access-date = December 4, 2019 | archive-date = October 9, 2010 | archive-url = https://web.archive.org/web/20101009002721/https://adblockplus.org/en/about | url-status = live }}</ref>

===uBlock Origin=== On April 3, 2015, Raymond Hill transferred the uBlock project to Chris Aljoudi due to frustrations with managing increasing user requests.<ref>{{Citation |last=Hill |first=Raymond |title=Release 0.9.3.0 |date=2015-04-03 |work=gorhill/uBlock |url=https://github.com/gorhill/uBlock/releases/tag/0.9.3.0 |access-date=2023-12-08 |language=en |archive-date=January 24, 2025 |archive-url=https://web.archive.org/web/20250124231911/https://github.com/gorhill/uBlock/releases/tag/0.9.3.0 |url-status=live }}</ref> Hill explained that it was no longer a hobby: "These projects are to me, not a full-time job. It stopped being a hobby when it felt more and more like a tedious job. I will keep maintaining my version (and share with whoever cares to use it) because it guarantees the tool will match what I want out of it."<ref>{{cite web |last=Hill |first=Raymond |title=Please clarify uBlock<sub>0</sub> vs. uBlock |url=https://github.com/gorhill/uBlock/issues/38 |access-date=December 4, 2019 |website=Github.com |archive-date=January 5, 2022 |archive-url=https://web.archive.org/web/20220105184531/https://github.com/gorhill/uBlock/issues/38 |url-status=live }}</ref> On April 6, Hill created his own fork of the project, naming it uBlock Origin.<ref>{{Citation |last=Hill |first=Raymond |title=Update README.md |url=https://github.com/gorhill/uBlock/commit/353ce96c26b520e3f69c49b72e60786813fd528e |access-date=2023-12-08 |language=en |archive-date=December 12, 2024 |archive-url=https://web.archive.org/web/20241212200952/https://github.com/gorhill/uBlock/commit/353ce96c26b520e3f69c49b72e60786813fd528e |url-status=live }}</ref>

Since October 2017, uBlock Origin has been completely separated from Aljoudi's uBlock.<ref>{{cite web |last=Hill |first=Raymond |date=October 21, 2017 |title=uBlock Origin is completely unrelated to the web site ublock.org |url=https://github.com/gorhill/uBlock/wiki/uBlock-Origin-is-completely-unrelated-to-the-web-site-ublock.org |access-date=December 4, 2019 |website=github.com |archive-date=February 9, 2022 |archive-url=https://web.archive.org/web/20220209170141/https://github.com/gorhill/uBlock/wiki/uBlock-Origin-is-completely-unrelated-to-the-web-site-ublock.org |url-status=live }}</ref> Aljoudi created ublock.org to host and promote uBlock and to request donations. In response, Hill stated that "the donations sought by ublock.org are not benefiting any of those who contributed most to create uBlock Origin."<ref name="gorhill_readme" />

=== uBlock Origin Lite === In 2023, Google made changes known as "Manifest V3" (MV3 in short) to the WebRequest API used by ad blocking and privacy extensions to block and modify network connections.<ref name=":1">{{Cite web |last=Amadeo |first=Ron |date=2023-11-21 |title=Google Chrome will limit ad blockers starting June 2024 |url=https://arstechnica.com/gadgets/2023/11/google-chrome-will-limit-ad-blockers-starting-june-2024/ |url-status=live |archive-url=https://web.archive.org/web/20231122183429/https://arstechnica.com/gadgets/2023/11/google-chrome-will-limit-ad-blockers-starting-june-2024/ |archive-date=November 22, 2023 |access-date=2023-11-22 |website=Ars Technica |language=en-us}}</ref><ref>{{Cite web |last=Tung |first=Liam |title=Google Chrome could soon kill off most ad-blocker extensions |url=https://www.zdnet.com/article/google-chrome-could-soon-kill-off-most-ad-blocker-extensions/ |url-status=live |archive-url=https://web.archive.org/web/20201219125215/https://www.zdnet.com/article/google-chrome-could-soon-kill-off-most-ad-blocker-extensions/ |archive-date=December 19, 2020 |access-date=June 13, 2019 |website=ZDNet |language=en}}</ref> Following Google's implementation of Manifest V3 and the end of support for V2 (which was ultimately implemented in March 2025),<ref name=":7">{{Cite web |last=Weatherbed |first=Jess |date=2025-03-03 |title=Google's Chrome extension cull hits more uBlock Origin users |url=https://www.theverge.com/news/622953/google-chrome-extensions-ublock-origin-disabled-manifest-v3 |access-date=2025-03-03 |website=The Verge |language=en-US |archive-date=August 22, 2025 |archive-url=https://web.archive.org/web/20250822220411/https://www.theverge.com/news/622953/google-chrome-extensions-ublock-origin-disabled-manifest-v3 |url-status=live }}</ref> uBlock Origin's effectiveness was drastically reduced in Google Chrome and other Chromium-based browsers.<ref>{{cite web |date=December 9, 2021 |title=Chrome Users Beware: Manifest V3 is Deceitful and Threatening |url=https://www.eff.org/deeplinks/2021/12/chrome-users-beware-manifest-v3-deceitful-and-threatening |access-date=April 25, 2024 |archive-date=May 16, 2023 |archive-url=https://web.archive.org/web/20230516085941/https://www.eff.org/deeplinks/2021/12/chrome-users-beware-manifest-v3-deceitful-and-threatening |url-status=live }}</ref><ref>{{cite web |title=uBO Lite |url=https://github.com/uBlockOrigin/uBOL-home |website=GitHub |access-date=April 25, 2024 |archive-date=April 25, 2024 |archive-url=https://web.archive.org/web/20240425004017/https://github.com/uBlockOrigin/uBOL-home |url-status=live }}</ref><ref>{{cite web |title=More details on the transition to Manifest V3 |url=https://developer.chrome.com/blog/more-mv2-transition/ |access-date=April 25, 2024 |archive-date=August 6, 2025 |archive-url=https://web.archive.org/web/20250806095014/https://developer.chrome.com/blog/more-mv2-transition |url-status=live }}</ref>

As a result, uBlock Origin Lite was created and designed to comply with the new extension framework. uBO Lite differs from uBO in several key aspects, primarily due to the constraints and design goals associated with Manifest V3. Specifically, it lacks filter list updates outside of extension updates, and has no custom filters, strict-blocked pages, per-site switches, or dynamic filtering. Google has been criticized for implementing some of these features due to its domination (Google Ads) in the online advertising market.<ref>{{Cite web |last=Cyphers |first=Bennett |date=2019-08-30 |title=Don't Play in Google's Privacy Sandbox |url=https://www.eff.org/deeplinks/2019/08/dont-play-googles-privacy-sandbox-1 |access-date=2024-04-25 |website=Electronic Frontier Foundation |language=en |archive-date=April 27, 2024 |archive-url=https://web.archive.org/web/20240427192044/https://www.eff.org/deeplinks/2019/08/dont-play-googles-privacy-sandbox-1 |url-status=live }}</ref><ref>{{Cite web |last=O'Reilly |first=Lara |title=Google is once again dictating the future of the online ad industry and all its rivals can do is brace for impact |url=https://www.businessinsider.com/googles-cookie-delay-underscores-its-ad-industry-dominance-2024-4 |url-access=registration |access-date=2024-04-25 |website=Business Insider |language=en-US |archive-date=August 16, 2025 |archive-url=https://web.archive.org/web/20250816224540/https://www.businessinsider.com/googles-cookie-delay-underscores-its-ad-industry-dominance-2024-4 |url-status=live }}</ref><ref>{{Cite web |last=Cyphers |first=Alexei Miagkov and Bennett |date=2021-12-14 |title=Google's Manifest V3 Still Hurts Privacy, Security, and Innovation |url=https://www.eff.org/deeplinks/2021/12/googles-manifest-v3-still-hurts-privacy-security-innovation |access-date=2024-04-25 |website=Electronic Frontier Foundation |language=en |archive-date=August 23, 2025 |archive-url=https://web.archive.org/web/20250823161358/https://www.eff.org/deeplinks/2021/12/googles-manifest-v3-still-hurts-privacy-security-innovation |url-status=live }}</ref><ref>{{Cite web |last=Claburn |first=Thomas |date=2022-09-08 |title=Ad blockers struggle under Chrome's new rules |url=https://www.theregister.com/2022/09/08/ad_blockers_chrome_manifest_v3/ |access-date=2024-04-26 |website=The Register |language=en |archive-date=August 20, 2025 |archive-url=https://web.archive.org/web/20250820122237/https://www.theregister.com/2022/09/08/ad_blockers_chrome_manifest_v3/ |url-status=live }}</ref>

Following a dispute with Mozilla add-on administrators over perceived security flaws, Raymond Hill pulled uBlock Origin Lite from the Firefox Marketplace in August 2025.<ref>{{Cite web |title=Popular ad blocker uBlock Origin Lite pulled from Firefox store |url=https://www.pcworld.com/article/2474353/popular-ad-blocker-removed-from-firefox-extension-store.html |access-date=2025-08-17 |website=PCWorld |language=en |archive-date=September 8, 2025 |archive-url=https://web.archive.org/web/20250908223459/https://www.pcworld.com/article/2474353/popular-ad-blocker-removed-from-firefox-extension-store.html |url-status=live }}</ref> The classic (MV2) version is unaffected and is still developed for Firefox, which is its preferred platform. Subsequently, community developers created a sideloaded version for Firefox via GitHub.<ref>{{Citation |title=uBlockOrigin/uBOL-home |date=2025-09-29 |url=https://github.com/uBlockOrigin/uBOL-home |access-date=2025-09-29 |publisher=uBlockOrigin |archive-date=April 25, 2024 |archive-url=https://web.archive.org/web/20240425004017/https://github.com/uBlockOrigin/uBOL-home |url-status=live }}</ref>

Researchers from Goethe University Frankfurt, compared uBOL vs uBO performance and confirmed that uBOL managed to bypass most of Google's restrictions in MV3. The tested MV3 extension were found blocking as many requests to trackers and ads to their MV2 counterpart (quantitative study).<ref>{{cite arXiv |last1=Lukic |first1=Karlo |last2=Papadopoulos |first2=Lazaros |title =Privacy vs. Profit: The Impact of Google's Manifest Version 3 (MV3) Update on Ad Blocker Effectiveness|date=2025 |class=cs.CY |eprint=2503.01000v2 |language=en}}</ref> However, the researchers also found that cosmetic filters were over 20% less effective in the tested sample (visual study).<ref name=":8">{{cite arXiv |last1=Lukic |first1=Karlo |last2=Papadopoulos |first2=Lazaros |title= Privacy vs. Profit: The Impact of Google's Manifest Version 3 (MV3) Update on Ad Blocker Effectiveness|date=2025 |class=cs.CY |eprint=2503.01000v2 |language=en}}</ref> The study also found that uBOL on average blocked more trackers than AdBlock, AdGuard, and Stands extension.<ref name=":8" />

As of March 2026, the Chrome version of uBlock Origin Lite has over 16 million active users.<ref>{{Cite web |title=uBlock Origin Lite - Chrome Web Store |url=https://chromewebstore.google.com/detail/ublock-origin-lite/ddkjiahejlhfcafbddmgiahcphecmpfh |access-date=2026-03-04 |website=chromewebstore.google.com |language=en-US |archive-date=August 22, 2025 |archive-url=https://web.archive.org/web/20250822222131/https://chromewebstore.google.com/detail/ublock-origin-lite/ddkjiahejlhfcafbddmgiahcphecmpfh |url-status=live }}</ref>{{Better source needed|reason=The current source is insufficiently reliable (WP:NOTRS).|date=March 2025}}

==Features== ===Blocking and filtering=== uBlock Origin supports the majority of Adblock Plus's filter syntax. The popular filter lists ''EasyList'' and ''EasyPrivacy'' are enabled by default. The extensions are capable of importing hosts files and a number of community-maintained lists are available at installation. Among the host files available, ''Peter Lowe's ad servers & tracking list'' and lists of malware domains such as uBlock Origin's own anti-malicious filter called ''Badware risks'' are also enabled as default, preventing users from visiting malicious websites such as those used for phishing, scams, malware, and more.<ref>{{Cite web |title=uAssets/filters/badware.txt at master · uBlockOrigin/uAssets |url=https://github.com/uBlockOrigin/uAssets/blob/master/filters/badware.txt |access-date=2024-08-03 |website=GitHub |language=en |archive-date=July 23, 2024 |archive-url=https://web.archive.org/web/20240723032100/https://github.com/uBlockOrigin/uAssets/blob/master/filters/badware.txt |url-status=live }}</ref> Some additional features include dynamic filtering of scripts and iframes and a tool for webpage element hiding.{{Citation needed|date=September 2023}}

uBlock Origin offers several features not found in the original uBlock. These include: * '''Color Vision Deficiency Mode''': A feature designed to assist users with color blindness. * '''Dynamic URL Filtering''': An option for more flexible and adaptive URL filtering. * '''Logging Functionality''': Allows users to view logs for better insight into the extension's activities. * '''DOM Inspector''': A tool for inspecting the Document Object Model of web pages. * '''Block link prefetching''': Prevents the browser from preloading or prefetching links. * '''Block hyperlink auditing''': Disables the ability of websites to track when links are clicked through a technique called hyperlink auditing.

There used to be a feature that protected against IP address leaks via WebRTC. However, this feature was removed in version 1.38 for all platforms except Android, as most browsers no longer have vulnerabilities related to WebRTC leaks.<ref>{{cite web |title=Prevent WebRTC from leaking local IP address |url=https://github.com/gorhill/uBlock/wiki/Prevent-WebRTC-from-leaking-local-IP-address |access-date=May 5, 2023 |website=GitHub, gorhill/uBlock |archive-date=February 21, 2016 |archive-url=https://web.archive.org/web/20160221222622/https://github.com/gorhill/uBlock/wiki/Prevent-WebRTC-from-leaking-local-IP-address |url-status=live }}</ref>

Site-specific switches to toggle the blocking of pop-ups, strict domain blocking, cosmetic filtering, blocking remote fonts, and JavaScript disabling were also added to uBlock Origin.<ref>{{cite web|title=uBlock wiki|url=https://github.com/gorhill/uBlock/wiki|website=GitHub|access-date=June 13, 2015|archive-date=February 15, 2022|archive-url=https://web.archive.org/web/20220215185337/https://github.com/gorhill/uBlock/wiki|url-status=live}}</ref> The Firefox version of uBlock Origin has an extra feature which helps to foil attempts by web sites to circumvent blockers.<ref>{{cite web |title=Inline script tag filtering – Overwiew |url=https://github.com/gorhill/uBlock/wiki/Inline-script-tag-filtering#overview |access-date=March 20, 2017 |website=GitHub, gorhill/uBlock |archive-date=February 19, 2020 |archive-url=https://web.archive.org/web/20200219083059/https://github.com/gorhill/uBlock/wiki/Inline-script-tag-filtering#overview |url-status=live }}</ref>

uBlock Origin also supports modifying the response body of a request using the <code>=replace</code> directive. This allows it to effectively alter and deliver the modified response directly to the browser. However, this functionality is currently supported only on Firefox and Firefox-based browsers.<ref>{{Cite web |title=Implement network filter option 'replace=' · gorhill/uBlock@7c3e060 |url=https://github.com/gorhill/uBlock/commit/7c3e060c01 |access-date=2025-05-20 |website=GitHub |language=en |archive-date=May 22, 2025 |archive-url=https://web.archive.org/web/20250522121834/https://github.com/gorhill/uBlock/commit/7c3e060c01 |url-status=live }}</ref>

===Performance and efficiency=== Technology websites and user reviews for uBlock Origin have regarded the extension as less resource-intensive than extensions that provide similar feature sets such as Adblock Plus.<ref name="lynch_firefox">{{cite web|url=http://jimlynch.com/internet/ublock-ad-blocker-added-to-mozillas-extensions-site/|title=uBlock ad blocker added to Mozilla's extensions site|website=Jim Lynch, Technology and Other Musings|archive-url=https://archive.today/20150609011416/http://jimlynch.com/internet/ublock-ad-blocker-added-to-mozillas-extensions-site/|archive-date=June 9, 2015|url-status=dead|access-date=February 17, 2015}}</ref><ref name=":4">{{Cite web|url=http://rootmygalaxy.net/ublock-origin-vs-adblock-plus-adblocker-choose-2017/|archive-url=https://web.archive.org/web/20171028150409/http://rootmygalaxy.net/ublock-origin-vs-adblock-plus-adblocker-choose-2017/|url-status=usurped|archive-date=October 28, 2017|title=Adblock Plus vs uBlock Origin {{!}} Which one to Choose In 2017? {{!}} RMG|last=Kesari|first=Varun|website=rootmygalaxy.net|date=October 28, 2017 |language=en-US|access-date=October 28, 2017}}</ref><ref name=":5">{{Cite news |last=Harper |first=Christopher |date=May 2, 2015 |title=uBlock Origin - Better Than AdBlock Plus? |url=https://www.maketecheasier.com/ublock-origin-better-than-adblock-plus/ |access-date=May 27, 2017 |work=Make Tech Easier |language=en-US |archive-date=February 26, 2020 |archive-url=https://web.archive.org/web/20200226232403/https://www.maketecheasier.com/ublock-origin-better-than-adblock-plus/ |url-status=live }}</ref> A benchmark test, conducted in August 2015 with ten blocking extensions, showed uBlock Origin as the most resource-efficient among the extensions tested.<ref>{{cite web|title=10 Ad Blocking Extensions Tested for Best Performance|url=https://www.raymond.cc/blog/10-ad-blocking-extensions-tested-for-best-performance/view-all/|website=Raymond Tech Resources|date=August 26, 2015|access-date=August 26, 2015|archive-date=January 5, 2022|archive-url=https://web.archive.org/web/20220105152159/https://www.raymond.cc/blog/10-ad-blocking-extensions-tested-for-best-performance/view-all/|url-status=dead}}</ref>

uBlock Origin surveys what style resources are required for an individual web page rather than relying on a universal style sheet. The extension takes a snapshot of the filters the user has enabled, which contributes to accelerated browser start-up speed when compared to retrieving filters from cache every time.<ref>{{cite web|title=Notes on memory benchmarks, selfies|url=https://github.com/gorhill/uBlock/wiki/Notes-on-memory-benchmarks,-selfies|website=uBlock GitHub documentation|access-date=February 17, 2015|archive-date=February 9, 2022|archive-url=https://web.archive.org/web/20220209170254/https://github.com/gorhill/uBlock/wiki/Notes-on-memory-benchmarks,-selfies|url-status=live}}</ref>

==== Differential updates ==== Starting with version 1.54, uBlock Origin introduced the implementation of differential updates (delta updates), which allows the extension to fetch only changes to filter lists rather than downloading the entire list. This results in lower bandwidth consumption and more frequent updates. This change was part of uBlock Origin's efforts to reduce both requests and bandwidth usage, with the goal of not being ranked among the most bandwidth-intensive projects on jsDelivr, as reflected in public statistics.<ref>{{Cite web |title=Release 1.54.0 · gorhill/uBlock |url=https://github.com/gorhill/uBlock/releases/tag/1.54.0 |access-date=2024-10-20 |website=GitHub |language=en |archive-date=September 20, 2024 |archive-url=https://web.archive.org/web/20240920191253/https://github.com/gorhill/uBlock/releases/tag/1.54.0 |url-status=live }}</ref><ref>{{Cite web |title=Usage Statistics |url=https://www.jsdelivr.com/statistics |access-date=2024-10-20 |website=jsDelivr |language=en |archive-date=October 21, 2024 |archive-url=https://web.archive.org/web/20241021140827/https://www.jsdelivr.com/statistics |url-status=live }}</ref>

==== Environmental impact ==== According to a research paper, uBlock Origin was able to reduce web page load times by 28.5%, the highest efficiency compared to other ad blockers like AdBlock Plus and Privacy Badger. Its use could significantly reduce energy consumption, saving an estimated 100 hours of browsing time annually for the average global user.<ref name=":3">{{Cite journal |last=Pearce |first=Joshua M. |date=June 2020 |title=Energy Conservation with Open Source Ad Blockers |journal=Technologies |language=en |volume=8 |issue=2 |pages=18 |doi=10.3390/technologies8020018 |doi-access=free |issn=2227-7080}}</ref>

If widely adopted in the United States, it could save over $117 million per year in electricity costs, and globally, it could result in savings exceeding $1.8 billion. The research report also suggests that widespread use of uBlock Origin could have environmental benefits, potentially preventing pollution-related deaths caused by coal-fired power generation used to support the extra energy consumption from ads.<ref name=":3" />

=== Limitations in Chromium-based browsers === According to Raymond Hill, the creator and lead developer of the extension, uBlock Origin works best on Firefox.<ref>{{Cite web |title=uBlock Origin works best on Firefox |url=https://github.com/gorhill/uBlock/wiki/uBlock-Origin-works-best-on-Firefox |access-date=2024-10-20 |website=GitHub |language=en |archive-date=September 6, 2024 |archive-url=https://web.archive.org/web/20240906143347/https://github.com/gorhill/uBlock/wiki/uBlock-Origin-works-best-on-Firefox |url-status=live }}</ref> The main reason is that uBlock Origin (uBO) faces several technical limitations when used on Chromium-based browsers compared to its performance on Firefox, and as a result, users may experience less effective ad blocking, potential exposure to unwanted content, and slower performance when using uBO on Chromium-based browsers:<ref>{{Cite web |title=uBlock Origin works best on Firefox |url=https://github.com/gorhill/uBlock/wiki/uBlock-Origin-works-best-on-Firefox |access-date=2024-09-03 |website=GitHub |language=en |archive-date=September 6, 2024 |archive-url=https://web.archive.org/web/20240906143347/https://github.com/gorhill/uBlock/wiki/uBlock-Origin-works-best-on-Firefox |url-status=live }}</ref>

==== CNAME Uncloaking ==== In November 2019, a uBlock Origin user reported a novel technique used by some sites to bypass third-party tracker blocking. These sites link to URLs that are sub-domains of the page's domain, but those sub-domains resolve to third-party hosts via a CNAME record. Since the initial URL contained a sub-domain of the current page, it was interpreted by browsers as a first-party request and so was allowed by the filtering rules in uBlock Origin (and in similar extensions). The uBlock Origin developer came up with a solution using a DNS API which is exclusive to Firefox 60+.<ref>{{Cite web |title=uBlock Origin Now Blocks Sneaky First-Party Trackers in Firefox |url=https://www.bleepingcomputer.com/news/security/ublock-origin-now-blocks-sneaky-first-party-trackers-in-firefox/ |access-date=February 26, 2020 |website=BleepingComputer |language=en-us |archive-date=April 29, 2020 |archive-url=https://web.archive.org/web/20200429181624/https://www.bleepingcomputer.com/news/security/ublock-origin-now-blocks-sneaky-first-party-trackers-in-firefox/ |url-status=live }}</ref> The new feature was implemented in uBlock Origin 1.25, released on February 19, 2020.<ref>{{Cite web |title=uBlock Origin 1.25 Now Blocks Cloaked First-Party Scripts, Firefox Only |url=https://www.bleepingcomputer.com/news/security/ublock-origin-125-now-blocks-cloaked-first-party-scripts-firefox-only/ |access-date=February 26, 2020 |website=BleepingComputer |language=en-us |archive-date=February 25, 2020 |archive-url=https://web.archive.org/web/20200225192800/https://www.bleepingcomputer.com/news/security/ublock-origin-125-now-blocks-cloaked-first-party-scripts-firefox-only/ |url-status=live }}</ref>

Chromium-based browsers lack the ability to uncloak third-party servers disguised as first-party through CNAME records. This limitation reduces the efficiency of blocking third-party trackers, a capability that uBO fully utilizes on Firefox.

Furthermore: * '''IP address filtering''': In version 1.60, uBO introduced the ability to block network requests based on their IP addresses. This is achieved by fetching the DNS records for a specific URL and filtering according to the IPs found. Full support is available for Firefox-based browsers, while Chromium-based browsers can only filter when an IP address is directly used in the URL instead of a hostname. * '''HTML Filtering''': uBO's ability to filter the response body of HTML documents before they are parsed by the browser is hindered in Chromium-based browsers. This feature, enabled by the <code>webRequest.filterResponseData()</code> API, is currently only available in Firefox, limiting the effectiveness of uBO's HTML filtering on Chromium-based platforms. * '''Response Body Filtering''': The <code>replace=</code> option in network filtering, which allows for response body modification, is less effective in Chromium-based browsers. Firefox's support for this feature enables more robust content manipulation. * '''Browser Launch Filtering''': On Chromium-based browsers, uBO may not be fully ready to block network requests from already opened tabs immediately upon browser launch. This can allow some tracker or advertisement payloads to load before uBO becomes active, which is especially problematic for users who utilize default-deny modes for third-party resources or JavaScript. While there is a mitigation setting available, it is not enabled by default and does not cover all use cases. * '''Pre-fetching''': In Chromium-based browsers, websites may override user settings regarding pre-fetching, potentially leading to unwanted network requests. Firefox, in contrast, reliably prevents pre-fetching when it is disabled in uBO. * '''WebAssembly Usage''': uBO does not use WebAssembly for core filtering code paths on Chromium-based browsers due to the additional permissions required in the extension manifest, which could complicate the extension's publication in the Chrome Web Store. This limitation can affect performance and functionality. * '''Storage Compression''': uBO on Chromium-based browsers cannot effectively use LZ4 compression for storing filter lists and other data due to issues with IndexedDB in incognito mode. IndexedDB instances are reset in incognito mode, causing uBO to start with out-of-date filter lists and reduced efficiency. Firefox does not face this issue, allowing for more efficient storage and retrieval of data.

== Reception == uBlock Origin is a widely praised content-filtering extension, known for being less memory-intensive than similar tools.<ref>{{cite web |last=Henry |first=Alan |date=January 27, 2015 |title=uBlock, the Memory-Friendly Ad-Blocker, Is Now Available for Firefox |url=https://lifehacker.com/ublock-the-memory-friendly-ad-blocker-is-now-availabl-1681818949 |access-date=December 4, 2019 |archive-date=January 28, 2015 |archive-url=https://web.archive.org/web/20150128151342/https://lifehacker.com/ublock-the-memory-friendly-ad-blocker-is-now-availabl-1681818949 |url-status=live }}</ref><ref>{{cite web |last=Brinkmann |first=Martin |date=October 10, 2014 |title=How to add custom filters to Chrome ad-blocking extension μBlock |work=gHacks Technology News |url=https://www.ghacks.net/2014/10/10/how-to-add-custom-filters-to-chrome-ad-blocking-extension-%C2%B5block/ |access-date=December 4, 2019}}</ref><ref>{{cite web |last=Schofield |first=Jack |date=January 29, 2015 |title=Are there any trustworthy sources for downloading software? |url=https://www.theguardian.com/technology/askjack/2015/jan/29/are-there-any-trustworthy-sources-for-downloading-software |access-date=December 4, 2019 |website=TheGuardian.com |archive-date=January 7, 2022 |archive-url=https://web.archive.org/web/20220107052156/https://www.theguardian.com/technology/askjack/2015/jan/29/are-there-any-trustworthy-sources-for-downloading-software |url-status=live }}</ref><ref>{{cite web |last=Whitwam |first=Ryan |date=February 12, 2015 |title=μBlock aims to block ads without draining system resources |url=https://www.extremetech.com/computing/199188-%C2%B5block-aims-to-block-ads-without-draining-system-resources |url-status=dead |archive-url=https://web.archive.org/web/20200324081014/https://www.extremetech.com/computing/199188-%C2%B5block-aims-to-block-ads-without-draining-system-resources |archive-date=March 24, 2020 |access-date=December 4, 2019 |website=ExtremeTech.com}}</ref> Its primary purpose is to give users control over their content-filtering choices, particularly in blocking advertisements and enhancing privacy.<ref>{{cite web |title=uBlock |url=https://github.com/gorhill/uBlock |access-date=December 4, 2019 |website=github.com |publisher=GitHub |archive-date=February 25, 2017 |archive-url=https://web.archive.org/web/20170225131009/https://github.com/gorhill/uBlock |url-status=live }}</ref><ref>{{cite news |last=Gardiner |first=Michael |date=November 5, 2015 |title=Adblock Plus vs. Ghostery vs. Ublock Origin: Not All Adblockers Were Created Equal |url=http://www.idigitaltimes.com/adblock-plus-vs-ghostery-vs-ublock-origin-not-all-adblockers-were-created-equal-488257 |url-status=dead |archive-url=https://web.archive.org/web/20170722210926/http://www.idigitaltimes.com/adblock-plus-vs-ghostery-vs-ublock-origin-not-all-adblockers-were-created-equal-488257 |archive-date=July 22, 2017 |access-date=December 4, 2019 |work=International Business Times}}</ref>

The extension has received positive feedback from both users and academic researchers. It is frequently recognized for its effectiveness in blocking ads, improving privacy, and boosting browsing efficiency.<ref name="lynch_firefox" /><ref name=":4" /><ref name=":5" /> Numerous studies and scientific papers have examined uBlock Origin's impact on web performance, privacy, and user experience. These studies have contributed to a better understanding of the benefits of ad-blocking tools, with uBlock Origin often cited as one of the most comprehensive and efficient solutions. Its widespread use and inclusion in academic research highlight its importance in the broader context of digital privacy and online security.<ref>{{Cite web |title=Scientific papers |url=https://github.com/gorhill/uBlock/wiki/Scientific-papers |access-date=2024-12-26 |website=GitHub |language=en |archive-date=December 26, 2024 |archive-url=https://web.archive.org/web/20241226143816/https://github.com/gorhill/uBlock/wiki/Scientific-papers |url-status=live }}</ref>

uBlock Origin is also appreciated for its commitment to remaining a non-profit project.<ref>{{cite web |title=MANIFESTO.md |url=https://github.com/gorhill/uBlock/blob/master/MANIFESTO.md |access-date=December 4, 2019 |website=github.com |archive-date=March 11, 2020 |archive-url=https://web.archive.org/web/20200311044913/https://github.com/gorhill/uBlock/blob/master/MANIFESTO.md |url-status=live }}</ref> It does not accept paid advertisements and refuses donations, encouraging users to support the maintainers of block lists directly.<ref>{{cite web |title=Why don't you accept donations? |url=https://github.com/gorhill/uBlock/wiki/Why-don%27t-you-accept-donations%3F |access-date=January 20, 2020 |website=GitHub |archive-date=February 21, 2020 |archive-url=https://web.archive.org/web/20200221215100/https://github.com/gorhill/uBlock/wiki/Why-don%27t-you-accept-donations%3F |url-status=live }}</ref> This commitment to independence helps reinforce its reputation as a privacy-focused tool without commercial interests.

Additionally, it has been praised for its positive environmental impact. By reducing web page load times, it can lead to significant energy savings. Widespread adoption of the tool could help lower energy consumption and mitigate environmental harm.<ref name=":3" />

==Supported platforms== uBlock Origin is actively developed for applications based on two major layout engines.<ref name="brinkmann_chrome" /><ref name="lynch_firefox" /><ref name="safari_ext">{{Cite web|url = https://extensions.apple.com/details/?id=net.gorhill.uBlock-96G4BAKDQ9|title = Apple - Safari - Safari Extensions Gallery|access-date = February 19, 2015|publisher = Apple|archive-date = March 10, 2016|archive-url = https://web.archive.org/web/20160310124626/https://extensions.apple.com/details/?id=net.gorhill.uBlock-96G4BAKDQ9|url-status = dead}}</ref>

With Google's phaseout of Manifest V2 in favor of Manifest V3, non-Chromium browsers like Firefox are unaffected.<ref>{{cite web |last=Brinkmann |first=Martin |date=September 24, 2022 |title=Mozilla reaffirms that Firefox will continue to support current content blockers |url=https://www.ghacks.net/2022/09/24/mozilla-reaffirms-that-firefox-will-continue-to-support-current-content-blockers/ |website=Ghacks Technology News |access-date=April 25, 2024 |archive-date=July 22, 2025 |archive-url=https://web.archive.org/web/20250722134556/https://www.ghacks.net/2022/09/24/mozilla-reaffirms-that-firefox-will-continue-to-support-current-content-blockers/ |url-status=live }}</ref> As of April 2025, Microsoft Edge supports uBlock Origin.<ref>{{cite web |title=Edge Add-ons uBlock Origin |url=https://microsoftedge.microsoft.com/addons/detail/ublock-origin/odfafepnkmbhccpbejgmiehpchacaeak |access-date=April 16, 2025 |archive-date=April 8, 2025 |archive-url=https://web.archive.org/web/20250408180720/https://microsoftedge.microsoft.com/addons/detail/ublock-origin/odfafepnkmbhccpbejgmiehpchacaeak |url-status=live }}</ref> Brave, another Chromium-based browser, has announced its intent to continue supporting MV2-based extensions such as uBlock Origin.<ref name=":6">{{Cite web |title=About Google Chrome's "This extension may soon no longer be supported" |url=https://github.com/gorhill/uBlock/wiki/About-Google-Chrome%27s-%22This-extension-may-soon-no-longer-be-supported%22 |access-date=2024-12-26 |website=GitHub |language=en |archive-date=December 26, 2024 |archive-url=https://web.archive.org/web/20241226151532/https://github.com/gorhill/uBlock/wiki/About-Google-Chrome%27s-%22This-extension-may-soon-no-longer-be-supported%22 |url-status=live }}</ref>

===Currently supported===

==== Chromium-based browsers ==== * Microsoft Edge * Brave * Opera

==== Gecko-based browsers ==== : Gecko-based browsers include * Firefox * Firefox for Android * Zen Browser

=== Limited support === * Google Chrome: Due to the phase-out of Manifest V2-based extensions since October 2024, uBlock Origin is marked as deprecated on the Chrome Web Store and is being remotely removed from Chrome installations.<ref name=":7" /><ref>{{Cite web |last=Roth |first=Emma |date=2024-10-15 |title=Google Chrome's uBlock Origin phaseout has begun |url=https://www.theverge.com/2024/10/15/24270981/google-chrome-ublock-origin-phaseout-manifest-v3-ad-blocker |access-date=2025-03-24 |website=The Verge |language=en-US |archive-date=December 21, 2024 |archive-url=https://web.archive.org/web/20241221053702/https://www.theverge.com/2024/10/15/24270981/google-chrome-ublock-origin-phaseout-manifest-v3-ad-blocker |url-status=live }}</ref> uBlock Origin Lite has been designed as a Manifest V3-based version with reduced functionality.<ref>{{Cite web |last=Roth |first=Emma |date=2024-10-15 |title=Google Chrome's uBlock Origin phaseout has begun |url=https://www.theverge.com/2024/10/15/24270981/google-chrome-ublock-origin-phaseout-manifest-v3-ad-blocker |access-date=2024-12-21 |website=The Verge |language=en |archive-date=December 21, 2024 |archive-url=https://web.archive.org/web/20241221053702/https://www.theverge.com/2024/10/15/24270981/google-chrome-ublock-origin-phaseout-manifest-v3-ad-blocker |url-status=live }}</ref> * Safari: Support for uBlock Origin in Safari had previously ended with macOS 10.15 Catalina because Apple deprecated the legacy Safari Extension API in favor of a restricted content blocker framework, which limited ad-blocking capabilities and was incompatible with uBO's functionality.<ref>{{Cite web |title=Catalina compatibility · Issue #156 · el1t/uBlock-Safari |url=https://github.com/el1t/uBlock-Safari/issues/156 |access-date=August 18, 2019 |website=github.com |language=en |archive-date=November 11, 2020 |archive-url=https://web.archive.org/web/20201111222653/https://github.com/el1t/uBlock-Safari/issues/156 |url-status=live }}</ref><ref name="safari_drop_ublock">{{cite web |title=Explanation of the state of uBlock Origin (and other blockers) for Safari |url=https://github.com/el1t/uBlock-Safari/issues/158 |website=GitHub |access-date=October 26, 2019 |archive-date=February 22, 2020 |archive-url=https://web.archive.org/web/20200222190619/https://github.com/el1t/uBlock-Safari/issues/158 |url-status=live }}</ref><ref name=":0">{{Cite web |title=el1t/uBlock-Safari |url=https://github.com/el1t/uBlock-Safari |access-date=January 19, 2017 |website=github.com |language=en |archive-date=January 27, 2022 |archive-url=https://web.archive.org/web/20220127180059/https://github.com/el1t/uBlock-Safari |url-status=live }}</ref><ref group="note">Unofficial release. Fork by ''[https://github.com/el1t Ellis Tsung (el1t)] {{Webarchive|url=https://web.archive.org/web/20170104081004/https://github.com/el1t |date=January 4, 2017 }}'' for Safari from the official project.</ref> However, in 2025, development resumed after Apple introduced the necessary components to Safari, and uBlock Origin Lite is again available via the App Store,<ref>{{Cite web |date=2025-08-07 |title=uBlock Origin Lite |url=https://apps.apple.com/us/app/ublock-origin-lite/id6745342698 |access-date=2025-08-12 |website=App Store |language=en-US |archive-date=August 13, 2025 |archive-url=https://web.archive.org/web/20250813165728/https://apps.apple.com/us/app/ublock-origin-lite/id6745342698 |url-status=live }}</ref> allowing users to install it on both macOS and iOS.<ref>{{Cite web |title=Safari issues to resolve for a minimally working uBOL · Issue #327 · uBlockOrigin/uBOL-home |url=https://github.com/uBlockOrigin/uBOL-home/issues/327 |access-date=2025-05-15 |website=GitHub |language=en |archive-date=May 14, 2025 |archive-url=https://web.archive.org/web/20250514065011/https://github.com/uBlockOrigin/uBOL-home/issues/327 |url-status=live }}</ref><ref>{{Cite web |title=Join the uBlock Origin Lite beta |url=https://testflight.apple.com/join/JjTcThrV |access-date=2025-05-15 |website=testflight.apple.com |language=en |archive-date=May 16, 2025 |archive-url=https://web.archive.org/web/20250516233821/https://testflight.apple.com/join/JjTcThrV |url-status=dead }}</ref> * Mozilla Thunderbird: In Thunderbird, uBlock Origin only affects RSS feeds, meaning that the content blocking and privacy protections provided by uBO are not possible for emails.

===Previously supported=== * Goanna ** Pale Moon: Previously users had to use the Firefox-legacy release, which was last updated on July 20, 2021.<ref>{{Citation |last=Hill |first=Raymond |title=gorhill/uBlock-for-firefox-legacy |date=2024-12-09 |url=https://github.com/gorhill/uBlock-for-firefox-legacy |access-date=2024-12-26 |archive-date=February 5, 2025 |archive-url=https://web.archive.org/web/20250205001608/https://github.com/gorhill/uBlock-for-firefox-legacy |url-status=live }}</ref> As a result, it is no longer supported and not recommended for daily use due to potential incompatibilities, security vulnerabilities, and inefficiencies in content blocking. There is a fork that fixes numerous bugs and tries to be closer to the main uBlock branch.<ref>{{Citation |last=UCyborg |title=UCyborg/uBlock-for-firefox-legacy |date=2025-01-11 |url=https://github.com/UCyborg/uBlock-for-firefox-legacy |access-date=2025-01-15 |archive-date=February 5, 2025 |archive-url=https://web.archive.org/web/20250205001608/https://github.com/UCyborg/uBlock-for-firefox-legacy |url-status=live }}</ref> The fork is the recommended ad-blocking extension for Pale Moon and its derivatives since early 2024 or so.<ref>{{Cite web |title=Pale Moon Add-ons - Search results for "ublock" |url=https://addons.palemoon.org/search/?terms=ublock |access-date=2025-01-15 |website=addons.palemoon.org |archive-date=December 9, 2024 |archive-url=https://web.archive.org/web/20241209122014/https://addons.palemoon.org/search/?terms=ublock |url-status=live }}</ref> * EdgeHTML ** Microsoft Edge Legacy: Edge Legacy was succeeded by Microsoft's complete rebuild of Edge, based on Chromium, on January 15, 2020. As a result, support for uBO ended shortly after, with the Chromium-based version of uBO taking its place.<ref name=":2">{{Citation |last=Rolls |first=Nik |title=nikrolls/uBlock-Edge |date=2021-06-12 |url=https://github.com/nikrolls/uBlock-Edge |access-date=2021-07-09 |archive-date=January 9, 2020 |archive-url=https://web.archive.org/web/20200109190151/https://github.com/nikrolls/uBlock-Edge |url-status=live }}</ref><ref name="microsoftedge">{{cite web |last1=Rubino |first1=Daniel |date=December 11, 2016 |title=uBlock Origin adblocker now available for Microsoft Edge via the Store |url=https://www.windowscentral.com/ublock-origin-available-microsoft-edge |access-date=December 12, 2016 |website=Windows Central |archive-date=December 12, 2016 |archive-url=https://web.archive.org/web/20161212062508/http://www.windowscentral.com/ublock-origin-available-microsoft-edge |url-status=live }}</ref><ref group="note">Unofficial release. Fork by ''[https://github.com/nikrolls/uBlock-Edge Nik Rolls (nikrolls)] {{Webarchive|url=https://web.archive.org/web/20200109190151/https://github.com/nikrolls/uBlock-Edge |date=January 9, 2020 }}'' for Microsoft Edge.</ref>

==See also== {{Portal|Free and open-source software|Internet }} * NoScript * Privacy Badger

== Notes == {{Reflist|group = note}}

==References== {{Reflist|30em}}

==External links== {{Commons category|UBlock}} * {{Official website|https://github.com/gorhill/uBlock}} * {{URL|https://chrome.google.com/webstore/detail/ublock-origin/cjpalhdlnbpafiamejdnhcphjbkeiagm|uBlock Origin on the Chrome Webstore}} * {{URL|https://chromewebstore.google.com/detail/ublock-origin-lite/ddkjiahejlhfcafbddmgiahcphecmpfh|uBlock Origin Lite on the Chrome Webstore}}

Category:2014 software Category:Ad blocking software Category:Advertising-free media Category:Firewall software Category:Free Firefox WebExtensions Category:Free security software Category:Google Chrome extensions Category:Internet privacy software Category:Internet properties established in 2014 Category:Online advertising Category:Software using the GNU General Public License