uBlock Origin
| uBlock Origin | |
|---|---|
uBlock Origin pop-up interface | |
| Original author | Raymond Hill (gorhill) |
| Developers | Current: Raymond Hill Past: Deathamns, Chris Aljoudi, Alex Vallat |
| Initial release | June 23, 2014 |
| Stable release | 1.70.0
/ 11 March 2026 |
| Written in | JavaScript |
| Operating system | Cross-platform |
| Predecessor | HTTP Switchboard and uMatrix |
| Available in | 72 languages |
| Type | Browser extension |
| License | GPLv3 |
| Repository | |
uBlock Origin (/ˈjuːblɒk/ YOO-blok) 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).
uBlock Origin is actively developed and maintained by its creator and lead developer Raymond Hill and the open source community. As of December 2025, 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.