Block ads on every device, without installing anything on them

A browser extension protects one browser. DNS-level blocking protects everything on the device: apps, smart TVs, consoles, the lot. Here is how it works, and where it stops.

How DNS ad blocking works

Before your phone loads an ad, it has to ask "where is doubleclick.net?" That question is a DNS lookup, and it happens before a single byte of the ad is fetched. A filtering resolver simply declines to answer for known ad and tracker domains, so the request never leaves the device.

Because every app on a device uses the same resolver, one setting covers your browser, your games, your smart TV and anything else on the network. There is nothing to install per app.

What it blocks well

• In-app advertising — the ads inside free mobile apps, which browser extensions cannot touch
• Trackers and telemetry — analytics SDKs that report on you from inside apps you already trust
• Smart-TV and IoT reporting — televisions are among the chattiest devices most people own
• Malware and phishing domains — the same mechanism, pointed at a different list

What it cannot block, honestly

Any guide that says DNS blocking stops all ads is selling something. It cannot:

• Block ads served from the same domain as the content. YouTube pre-roll comes from the same hosts as the video. DNS cannot tell them apart.
• Remove the gap where the ad was. DNS blocking prevents the fetch; it does not restyle the page.
• Survive a device that ignores your resolver. Some apps ship hard-coded DNS. Blocking the DoH providers used to bypass filtering is what closes that door.

Where DNSight differs

Blocking is the easy half, and every product on this list does it. The harder question is what happened on the device — which service, doing what, and in what order. DNSight keeps a readable timeline alongside the filtering: Opened Instagram — posted something, not rupload.facebook.com.

Protection packs apply per device, so the child's iPad can run a strict pack while the family TV runs none. Ad and tracker blocking is included on Pro and Expert plans.

Common questions

Does DNS ad blocking slow down my internet?

It usually speeds things up. Blocked lookups fail instantly instead of fetching an ad, so pages finish loading sooner and mobile battery lasts longer.

Does it work on cellular data?

Yes. Because the device points at an encrypted DNS endpoint rather than a network setting, filtering follows the device onto mobile data and onto other people's Wi-Fi.

Will it break websites?

Occasionally. Curated lists are tuned to avoid false positives, but any filter can catch something you wanted. Switching a device to a lighter pack takes a moment.

Do I need to install an app?

No. On iPhone and Mac it is a configuration profile; on a router it is a DNS setting that covers everything behind it.