UBlock Origin

uBlock Origin
Original author(s)Raymond Hill (gorhill)
Developer(s)Current:
Raymond Hill
Past:
Deathamns, Chris Aljoudi, Alex Vallat
Initial releaseJune 23, 2014 (2014-06-23)
Stable release
1.64.0 / 13 May 2025 (13 May 2025)
Repository
Written inJavaScript
Operating systemCross-platform
PredecessorHTTP Switchboard and uMatrix
Available in72 languages
TypeBrowser extension
LicenseGPLv3
Websitegithub.com/gorhill/uBlock

uBlock Origin (/ˈjblɒk/ 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 April 2025, the Chrome version of uBlock Origin had over 29 million active users and the Firefox version had over 9 million active users, making it the most popular extension on Firefox.