uBlock Origin - Free, open-source ad blocker
Easy on CPU and memory.
uBlock Origin is not just an “ad blocker“, it's a wide-spectrum content blocker with CPU and memory efficiency as a primary feature.
What Happened with Manifest V3
Updated: January 2026In late 2024, Google completed its transition to Manifest V3 in Chrome, which fundamentally changed how browser extensions work. As a result, the full version of uBlock Origin is no longer available for Chrome users. Here's what happened and what your options are now.
What Was Manifest V3?
Manifest V3 was Google's major update to the Chrome extension platform. The most significant change was replacing the webRequest API with the more limited declarativeNetRequest API. While Google cited security and performance benefits, this change removed capabilities that content blockers like uBlock Origin relied on for effective ad and tracker blocking.
How This Affected uBlock Origin
uBlock Origin used the webRequest API to intercept and block network requests in real-time. The replacement declarativeNetRequest API has hard limits on the number of filter rules (previously 30,000, now 330,000) and lacks the dynamic filtering capabilities that made uBlock Origin so effective. As a result, the full uBlock Origin extension was removed from the Chrome Web Store in late 2024. Chrome permanently disabled all remaining MV2 extensions in July 2025.
If You Use Chrome
uBlock Origin Lite is available for Chrome. This is a separate extension built specifically for Manifest V3, but it has significant limitations:
- Cannot use all filter lists simultaneously (rule limits apply)
- No cosmetic filtering in the default mode
- No scriptlet injection by default
- Limited dynamic filtering capabilities
- Requires broader host permissions upfront
If You Use Firefox or Brave
The full uBlock Origin extension continues to work on Firefox and Brave. Firefox has committed to supporting Manifest V2 extensions, and Brave has implemented workarounds to maintain full ad-blocker functionality. For the best content blocking experience, we recommend using one of these browsers.
Browser Support Summary
- Firefox: Full uBlock Origin support (recommended)
- Brave: Full uBlock Origin support
- Chrome/Chromium: uBlock Origin Lite only (limited functionality)
- Edge: Full uBlock Origin currently available, may follow Chrome's deprecation
- Safari: Not supported since version 13
Key Features
Open-source ad blocker
The uBlock Origin is a free and open-source, cross-platform browser extension for content filtering—primarily aimed at neutralizing privacy invasion in an efficient, user-friendly method.
CPU and memory efficiency
Globally, uBlock Origin could save consumers more than $1.8 billion/year (study (opens in new tab)). Open source ad blockers are a potentially effective technology for energy conservation.
Various browsers support
Full uBlock Origin support: Firefox (recommended), Brave. Limited support: Chrome/Chromium (uBO Lite only). Edge and Opera currently supported. Safari dropped after version 13.
About uBlock Origin
uBlock Origin blocks ads across websites including YouTube, Twitch, and other video platforms.
In 2014 uBlock Origin's founder, original author and lead developer, Raymond Hill, created the original uBlock extension, with its development initiated by forking the codebase of HTTP Switchboard with a separate blocking extension, uMatrix, which had been previously designed for advanced users. The initial uBlock was developed by Raymond Hill in order to enable community-maintained block lists while simultaneously adding additional features and upgrading the code quality to proper release standards. First released in June 2014 as an exclusive Chrome and Opera extension, in late 2015 the initial uBlock extension expanded to other browsers under its current name – uBlock Origin. (occasionally represented globally as – uBlock₀).
Following this 2015 introduction, a collaborative comsource and Sourcepoint industry research survey reported an 833% growth rate over a 10-month period ending in August 2016, the most rapid growth among any industry software publicly listed at that time. This report attributed this enormous surge to collective user demand for “pure” blockers with the capacity to operate outside the “acceptable advertising” program used by AdBlock, and other industry extensions.
Quickly gaining traction throughout the entire ad-blocking industry, the uBlock Origin Firefox version collected over 5 million active users, with its Chrome extension subsequently compiling over 10 million active users. Developer Nik Rolls then officially released uBlock Origin for the Microsoft Edge browser in December 2016.
In January 2017, uBlock Origin was added to the repositories for Debian 9, and Ubuntu (16.04), and the uBlock Origin extension was awarded the prestigious IoT honor of “Pick of the Month” by Mozilla.
As of 2026, uBlock Origin continues to be maintained and actively developed by founder and lead developer Raymond Hill.
The uBlock Origin extension remains an industry leading, open-source, cross-platform browser extension. As of 2026, the full extension is available for Firefox (recommended) and Brave. Chrome users can install uBlock Origin Lite, a reduced-functionality version built for Manifest V3. Edge and Opera currently support the full extension. Safari support was dropped after version 13.
The uBlock Origin project still specifically refuses donations at this time, and instead advises all of its clients, users and supporters to donate to block list maintainers.
Frequently Asked Questions
Does uBlock Origin block YouTube ads?
Yes. uBlock Origin blocks video ads on YouTube when using Firefox or Brave. Chrome users with uBlock Origin Lite may experience reduced effectiveness due to Manifest V3 limitations.
Does uBlock Origin work on Twitch?
Yes. uBlock Origin blocks ads on Twitch, though effectiveness may vary as Twitch updates their ad delivery methods. Filter lists are regularly updated to address changes.
Is uBlock Origin free?
Yes. uBlock Origin is completely free and open-source. The project does not accept donations and instead encourages users to support filter list maintainers.
What browsers support uBlock Origin?
Full support: Firefox (recommended), Brave. Limited support: Chrome (uBO Lite only). Also available for Edge and Opera. Safari support was discontinued after version 13.