Reputable ad blockers are safe to install. The question worth asking is not whether ad blockers in general are safe, but whether the specific ad blocker you’re considering is trustworthy. The wrong choice can expose you to an extension that is worse than the ads it claims to block.
What Permissions Do Ad Blockers Need?
Most ad blockers request the permission “Read and change all your data on all websites.” This sounds alarming, but it is required for any extension that needs to see and modify outgoing network requests — which is exactly what ad blocking requires (see how an ad blocker actually works). Without this permission, an extension cannot intercept requests to ad servers.
Having the permission does not mean the extension uses it to read your data. An ad blocker with this permission that makes no external calls (other than downloading filter lists) is not collecting your data — you can confirm this by watching its network activity in your browser’s developer tools.
How to Evaluate an Ad Blocker’s Safety
1. How is it funded?
An ad blocker has to pay for itself somehow. The three common models are a paid tier, an Acceptable Ads whitelist that advertisers pay to join, or data collection. If an extension has none of those, there is no incentive to let ads through or to track you.
ProBlocker has no paid tier, no Acceptable Ads, and collects no data.
uBlock Origin is donation-funded. AdBlock and Adblock Plus earn revenue from Acceptable Ads. For a rewards-based model, see our Pie Adblock review.
2. Does it have a history of incidents?
Search for the extension name along with “security” or “data collection” to check if there are documented issues. Some extensions have been caught injecting affiliate links or sending browsing data to third parties.
3. Who owns it?
AdBlock (not Adblock Plus) was acquired by Eyeo GmbH — the same company that runs the Acceptable Ads program. Both AdBlock and Adblock Plus now share the Acceptable Ads whitelist. Ownership and business model matter for evaluating long-term trust.
4. Does it have Acceptable Ads?
Acceptable Ads is not a security issue, but it is a transparency issue. An ad blocker that accepts payment from advertisers to allow their ads through has a financial relationship with the ad ecosystem it claims to block. Some users find this acceptable; others do not.
Ad blockers without Acceptable Ads →
Known Safe Ad Blockers
| Ad blocker | Data collection | Acceptable Ads | Price |
|---|---|---|---|
| ProBlocker | None | No | Free, no paid tier |
| uBlock Origin | None | No | Free |
| AdGuard | Limited (stated) | No | Free extension / paid apps |
| AdBlock | Unverifiable | Yes (default) | Free |
| Adblock Plus | Unverifiable | Yes (default) | Free |
Last verified: October 2026.
What Makes an Ad Blocker Unsafe?
Red flags to watch for (our Chrome extension safety guide has a fuller checklist):
- Not available in an official browser store (Chrome Web Store, Firefox Add-ons)
- Very few reviews or recently published with no track record
- Requests permissions unrelated to ad blocking (access to clipboard, camera, microphone)
- Closed source with no transparency report
- Name that closely mimics a well-known ad blocker (e.g., “AdBlock Pro”, “uBlock Plus”)
ProBlocker Safety Summary
ProBlocker is free with no paid tier, requires no account, and does not participate in Acceptable Ads. It requests the standard extension permission required for ad blocking. It makes no external calls during normal use except filter list downloads. It does not collect browsing history, IP addresses, search queries, or any personal data.
Read ProBlocker’s full transparency report →