AdBlock for Firefox vs AdBlocker Ultimate: Which Is Safer?
At a glance: verified facts
| Fact | AdBlock for Firefox | AdBlocker Ultimate |
|---|---|---|
| Published by | AdBlock | AdAvoid Ltd |
| Publisher public | Yes | Yes |
| Policy changes we track | None detected | None detected |
| Last data check | 2026-08-04 | 2026-08-04 |
From public records (the extension's store listing, publisher registry, manifest metadata) and our policy snapshots — a "—" means we have no verified data for that field yet.
What the evidence shows
Both are ad & content blockers extensions we track. Comparing the 5 safety dimensions measured for both:
- On publisher & identity, the two are evenly matched (60% vs 60%).
- AdBlocker Ultimate leads on permissions & access (90% vs 85%).
- AdBlocker Ultimate leads on data & privacy (100% vs 50%).
- On maintenance & ownership, the two are evenly matched (100% vs 100%).
- AdBlocker Ultimate leads on community reputation (100% vs 92%).
Safety score breakdown
| Dimension | AdBlock for Firefox | AdBlocker Ultimate |
|---|---|---|
| Publisher & Identity | 4.8/8 | 4.8/8 |
| Permissions & Access | 14.17/16.67 | 22.5/25 |
| Data & Privacy | 2/4 | 16/16 |
| Maintenance & Ownership | 7.5/7.5 | 7.5/7.5 |
| Community Reputation | 9.15/10 | 10/10 |
| Total | 81.48/100 | 91.43/100 |
Frequently asked questions
Is AdBlock for Firefox safer than AdBlocker Ultimate?
AdBlocker Ultimate currently scores higher — 91/100 vs 81/100 — across the 5 safety dimensions measured for both. That covers documented evidence only, not features or pricing.
Is AdBlock for Firefox safe?
AdBlock for Firefox currently holds safety grade A (81/100) based on 5 of 5 safety dimensions, and is published by AdBlock. The grade reflects only what we have measured; anything not yet assessed is marked as pending on the full report.
Is AdBlocker Ultimate safe?
AdBlocker Ultimate currently holds safety grade A (91/100) based on 5 of 5 safety dimensions, and is published by AdAvoid Ltd. The grade reflects only what we have measured; anything not yet assessed is marked as pending on the full report.
More Ad & Content Blockers extension comparisons
How this comparison works
Both extensions are scored with the same five-dimension, 100-point rubric — publisher & identity, permissions & access, data & privacy, maintenance & ownership and community reputation — using documented evidence only; a dimension with no evidence stays unscored instead of guessed. Read the full reports: AdBlock for Firefox safety report · AdBlocker Ultimate safety report, or run any other extension through the safety check.