uBlock Origin

Browser Install from ... Status : : Firefox Add-ons uBO works best on Firefox Edge Add-ons Opera Add-ons Chrome Web Store About Google Chrome's "This extension may soon no longer be supported" Removal from the Store on August 31st, 2026. Thunderbird Add-ons No longer updated and stuck at 1.49.2. Later versions require "GitHub - Releases". GitHub - Releases Stable 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][Blocking] for Chromium and Firefox. It blocks ads, trackers, coin miners, popups, annoying anti-blockers, malware sites, etc., by default using [EasyList][EasyList], [EasyPrivacy][EasyPrivacy], [Peter Lowe's Blocklist][Peter Lowe's Blocklist], [Online Malicious URL Blocklist][Malicious Blocklist], and uBO [filter lists][uBO Filters]. There are many other lists available to block even more. Hosts files are also supported. uBO uses the EasyList filter syntax and [extends][Extended Syntax] 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. 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. uBO [works best][Works Best] on Firefox and is available for desktop and Android versions. [Microsoft Edge Add-ons][Edge] (Published by [Nicole Rolls][Nicole Rolls] until version 1.62. Ownership transfer at version 1.64.) Do NOT use uBO with any other content blocker. uBO [performs][Performance] as well as or better than most popular blockers. Other blockers can prevent uBO's privacy or anti-blocker-defusing features from working correctly. 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.