Ad blockers · Firefox
The best ad blocker for Firefox in 2026
This is the easy one. Firefox runs the full uBlock Origin — the most powerful free ad blocker there is, and the one Chrome removed. If you're on Firefox, you already have access to the best free option going. Here's how to set it up, and the rare case for paying.
Last updated: July 10, 2026 · Browser extensions tested by the Privacy Intact team with our automated harness (June 8, 2026); see how we review.
The short answer
Install uBlock Origin. It's free, open-source, and on Firefox it runs at full strength — the very same full extension that topped our browser test at 96/100, the highest of anything we measured. There's very little reason to use anything else in the browser. You'd only reach for paid AdGuard if you want ads gone beyond Firefox — on your phone, or inside other apps.
Set it up in a minute
- Open the official uBlock Origin on Firefox Add-ons (developer: Raymond Hill / "gorhill" — check the name to avoid copycats).
- Click Add to Firefox → Add. That's it — default settings block the large majority of ads and trackers immediately.
- Optional: open uBlock's dashboard → Filter lists and confirm Auto-update is on, so it keeps working as sites change.
Leave Firefox's own Enhanced Tracking Protection on as well (Settings → Privacy & Security). It blocks many trackers and intrusive scripts at the browser level; uBlock Origin handles the ads on top. They complement each other.
Why Firefox runs the good version
Google's Manifest V3 change removed full uBlock Origin from Chrome and left only the lighter uBlock Origin Lite. Firefox chose to keep supporting the older, more capable extension model, so the full uBlock Origin — with real-time dynamic filtering, the element picker, and the rest — runs here untouched. That's the whole reason we point Chrome users who want free, powerful blocking toward Firefox. On Android, the same trick works: Firefox for Android runs uBlock Origin too.
When paid AdGuard still makes sense
To be straight with you: if your blocking needs stop at the Firefox window, you don't need to spend anything — uBlock Origin has you covered. The case for AdGuard is reach: its standalone app blocks ads across your whole device, including other apps and games and your phone, which no browser extension can. A one-time Lifetime license avoids a subscription, and direct purchases come with a 30-day money-back guarantee (check current terms). It also installs a local certificate to filter HTTPS — a real trust decision we cover in our AdGuard review and weigh in AdGuard vs uBlock Origin.
FAQ
Firefox ad-blocking, answered
What's the best ad blocker for Firefox?
uBlock Origin — and it isn't close. Firefox kept full support for the extension framework Chrome dropped, so the complete, most powerful uBlock Origin runs unrestricted here, free. In our own test the full version scored the highest of anything we measured. Install it from Firefox Add-ons and you're done. You'd only add a paid tool like AdGuard if you want blocking beyond the browser, on your phone or in other apps.
Is uBlock Origin safe?
Yes. uBlock Origin is free, open-source, and developed by Raymond Hill ('gorhill'); its code is public and widely audited by the community. It takes no payment, has no account, and runs no 'acceptable ads' whitelist. The only real risk is installing a copycat by mistake — get it from the official Firefox Add-ons listing and check the developer name.
Doesn't Firefox already block ads?
Not quite. Firefox's built-in Enhanced Tracking Protection blocks many trackers and some intrusive ads (cryptominers, fingerprinters), and it's worth leaving on — but it isn't a full ad blocker. For ads themselves, you still want uBlock Origin on top. The two work well together.
Is Firefox better than Chrome for blocking ads?
For free, in-browser blocking, yes — clearly. Chrome's Manifest V3 removed full uBlock Origin and left only the lighter uBO Lite; Firefox runs the full version untouched. If free, powerful ad-blocking matters to you, Firefox is the simplest fix. See our Chrome guide for what changed there.