gorhill

    gorhill/uBlock

    #783 this week

    uBlock Origin - An efficient blocker for Chromium and Firefox. Fast and lean.

    web
    blocker
    browser-extension
    chromium
    firefox
    javascript
    JavaScript
    GPL-3.0
    64.4K stars
    4.1K forks
    64.4K GitHub watchers
    Updated 6/23/2026
    View on GitHub

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    Use Cases & Benefits

    • uBlock Origin is a fast, efficient content blocker for Chromium and Firefox that blocks ads, trackers, malware, and more using multiple filter lists.
    • Key technologies include JavaScript, EasyList filter syntax with extended custom rules, and support for hosts files and dynamic filtering.
    • Strengths are high performance with low CPU/memory usage and wide browser support; limitations include end of support on Chrome 139 and manual updates for some browsers.
    • Organizations can deploy uBlock Origin enterprise-wide to enhance user privacy and security by blocking unwanted content and trackers efficiently.
    • Ideal use cases include privacy-conscious users, enterprises enforcing safe browsing, and developers needing customizable, lightweight ad-blocking solutions.

    About uBlock

    Badge Commits Badge Issues Badge Localization Badge License Badge NPM Badge Mozilla Badge Chrome Badge Edge


    uBlock Origin (uBO)

    BrowserInstall from ...Status
    Get uBlock Origin for FirefoxFirefox Add-onsuBO works best on Firefox
    Get uBlock Origin for Microsoft EdgeEdge Add-ons
    Get uBlock Origin for OperaOpera Add-ons
    Get uBlock Origin for ChromiumChrome Web StoreAbout Google Chrome's "This extension may soon no longer be supported"
    End of support on Chrome 139
    Get uBlock Origin for ThunderbirdThunderbird Add-onsNo longer updated and stuck at 1.49.2. Later versions require "GitHub - Releases".
    Get uBlock Origin through GitHubGitHub - ReleasesStable and development versions on Firefox, Chromium MV2, and Thunderbird. Must be placed manually into web browsers; the Chromium and Thunderbird versions usually won't auto-update.

    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.


    Documentation

    Basic ModeAdvanced 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.

    Installation

    Required Permissions

    Firefox

    Firefox Add-ons

    Development Builds

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

    Thunderbird

    Thunderbird Add-ons

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

    Chromium

    Chrome Web Store

    Microsoft Edge Add-ons (Published by Nicole Rolls until version 1.62. Ownership transfer at version 1.64.)

    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

    Translations

    Help translate uBO via Crowdin.

    About

    Manifesto

    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.

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