uBlock Origin

uBlock Origin
Original authorRaymond Hill (gorhill)
DevelopersCurrent:
Raymond Hill
Past:
Deathamns, Chris Aljoudi, Alex Vallat
ReleaseJune 23, 2014 (2014-06-23)
Stable release
1.74.0 / 25 August 2026 (25 August 2026)
Written inJavaScript
Operating systemCross-platform
PredecessorHTTP Switchboard and uMatrix
Available in72 languages
TypeBrowser extension
LicenseGPLv3
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 June 2026, the Chrome version of uBlock Origin had over 29 million active users and the Firefox version has over 10.6 million active users, making it the most popular extension on Firefox.