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DNS Block Test

Is your adblocker actually blocking?

Your browser tries to reach known ad, tracking, and malicious domains across seven categories. If your DNS blocks them, they fail. See exactly what is and is not getting through.

Works with AdGuard Home, Pi-hole, NextDNS, Cloudflare, and Harbor Privacy. Runs entirely in your browser -- no data leaves your device, nothing is logged.

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Run the test below to see your block score.
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Options
Include Harbor Kids / Family Safe NSFW check
Adult domains will be tested. Enable this only if you have the Family Protection add-on or want to verify Harbor Kids is working.
Ads & Banners
Pending
Trackers & Analytics
Pending
Social Media
Pending
Video Ads
Pending
Malware & Phishing
Pending
Cryptomining
Pending

How it works: your browser tries to open a network connection to each domain. If DNS blocks it, the connection never happens -- that is a pass. Domains span major ad networks, trackers, social widgets, video ad platforms, malware and phishing infrastructure, cryptomining scripts, and adult content -- the same categories AdGuard Home, Pi-hole, and NextDNS filter by default. Results are never sent anywhere.

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