uBlock Origin is a browser extension that blocks ads and trackers by filtering network requests against community-maintained lists, with dynamic filtering and per-site rules that can defeat even anti-adblock scripts. It runs entirely in your browser so it does nothing for other apps or devices. Chrome's move to Manifest V3 removed the webRequest API it relies on and Google disabled the last Manifest V2 extensions in mid-2025 so the full version now lives in Firefox and its forks. Pair it with a network-level blocker if you want coverage beyond the browser.
uBlock Origin
The gold-standard browser extension for blocking ads and trackers.
ublockorigin.comFreeOpen SourceWebOpen-source project
PricingFree and open-source, funded by donations; no paid tier and no "acceptable ads".
Strengths
- Powerful dynamic and per-site filtering
- Open-source (GPL-3.0), no monetized "acceptable ads"
- Very light on memory and CPU
Considerations
- Full version no longer runs in Chrome under Manifest V3
- Browser-only; nothing for other apps or devices
Listed inAd Blockers
uBlock Origin alternatives
NextDNSConfigurable DNS-level blocking for every device on your network.
uBlock Origin LiteThe Manifest V3 blocker for Chromium browsers, from uBO's own developer.
AdGuard DNSSet-in-minutes public DNS resolver that blocks ads and trackers.
Pi-holeSelf-hosted DNS blocker where your queries never leave your network.