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Raymond Hill a969a672e0
Change official description in source code top comment
4 hours ago
.github Remove obsolete workflow 2 weeks ago
assets Change official description in source code top comment 4 hours ago
dist Make Firefox dev build auto-update 5 hours ago
docs Fix typos in README, docs, and JS comments 2 years ago
platform Change official description in source code top comment 4 hours ago
src Change official description in source code top comment 4 hours ago
tools Ship minified version of lists in package 1 month ago
.gitignore git ignore ./tmp/ 8 years ago
.gitmodules Use `git clone` instead of submodule to pull uAssets dependencies 1 year ago
.jshintrc Refactor scriptlets injection code 9 months ago New revision for dev build 6 hours ago Update (#3889) 8 months ago
LICENSE.txt first commit 10 years ago Update (#3888) 8 months ago
Makefile Create a MVP version of uBOLite for Firefox 8 months ago Fix #2874 as suggested 2 months ago Move the repetitive portion of release notes to the bottom 4 weeks ago Added data about old popup panel 1 year ago

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uBlock Origin (uBO)

BEWARE! uBO is (and has always been) COMPLETELY UNRELATED to the website

Get uBlock Origin for Firefox Get uBlock Origin for Chromium Get uBlock Origin for Microsoft Edge Get uBlock Origin for Opera Get uBlock Origin for Thunderbird

uBlock Origin (uBO) is a CPU and memory-efficient wide-spectrum content blocker for Chromium and Firefox. It blocks ads, trackers, coin miners, popups, annoying anti-blockers, malware sites, etc., by default using EasyList, EasyPrivacy, Peter Lowe's Blocklist, Online Malicious URL Blocklist, and uBO filter lists. There are many other lists available to block even more. Hosts files are also supported. uBO uses the EasyList filter syntax and extends the syntax to work with custom rules and filters.

You may easily unselect any preselected filter lists if you think uBO blocks too much. For reference, Adblock Plus installs with only EasyList, ABP filters, and Acceptable Ads enabled by default.

It is important to note that using a blocker is NOT theft. Do not fall for this creepy idea. The ultimate logical consequence of blocking = theft is the criminalization of the inalienable right to privacy.

Ads, "unintrusive" or not, are just the visible portion of the privacy-invading means entering your browser when you visit most sites. uBO's primary goal is to help users neutralize these privacy-invading methods in a way that welcomes those users who do not wish to use more technical means.


Basic Mode Advanced Mode
The simple popup user interface for an install-it-and-forget-it type of installation that is configured optimally by default. The advanced popup user interface includes a point-and-click firewall that is configurable on a per-site basis.

Visit the Wiki for documentation.

For support, questions, or help, visit /r/uBlockOrigin.


Required Permissions


Firefox Add-ons

Development Builds

uBO works best on Firefox and is available for desktop and Android versions.


Thunderbird Add-ons

In Thunderbird, uBlock Origin does not affect emails, just feeds.


Chrome Web Store

Microsoft Edge Add-ons (Published by: Nicole Rolls)

Opera Add-ons

Development Builds

uBO should be compatible with any Chromium-based browser.

All Programs

Do NOT use uBO with any other content blocker. uBO performs as well as or better than most popular blockers. Other blockers can prevent uBO's privacy or anti-blocker-defusing features from working correctly.

Manual Installation

Enterprise Deployment

Deploying uBO

Release History

Releases Page


Help translate uBO via Crowdin.



Privacy Policy

GPLv3 License

Free. Open-source. For users by users. No donations sought.

If you ever want to contribute something, think about the people working hard to maintain the filter lists you are using, which are available to use by all for free.