DNS & ISP

How to Block Ads on Every Device at Home

Browser extensions only protect one browser. Apps on a phone only protect that phone. Smart TVs, game consoles and most apps cannot run an ad blocker at all. DNS blocking solves this by stopping ads and trackers before they ever load.

Last updated October 14, 2026 · By Harbor Privacy

How DNS Ad Blocking Works

Every time a device loads a page or an app, it first asks a DNS server to turn a name like ads.example.com into an address. A blocking DNS server looks the name up against a list of known ad and tracker domains. If the name is on the list, it answers with nothing, and the ad never loads.

Because the block happens at the name lookup, it works for anything that uses that DNS server: browsers, apps, smart TVs, consoles, and cheap smart-home gadgets. Nothing is installed on the device.

Three Ways to Do It

Change DNS on the routerEvery device on your Wi-Fi is covered automatically. Works only at home, and only if your router lets you set a custom DNS hostname.

Run it yourselfPi-hole or AdGuard Home on a Raspberry Pi or small server. Full control, but you maintain it, and if it goes down your whole house loses internet.

Use a hosted private DNSA service runs the blocking DNS for you and gives you an address to enter on each device or router. Works away from home too.

If you want to run your own, see AdGuard Home vs Pi-hole.

Setting It Up on the Router

This is the route that covers the whole house at once. Open your router's admin page and look for a setting called Private DNS, DNS over TLS, or custom DNS. Enter the hostname from your DNS provider and save.

Many consumer routers only accept plain IP addresses and not hostnames, so they cannot use encrypted DNS. In that case set up each device individually, which takes about a minute per device. A router guide is in the Harbor setup guide.

What DNS Blocking Cannot Do

Ads served from the same domain as the content. YouTube and some streaming apps serve ads and video from the same place, so DNS cannot separate them.
Blank spaces. A blocked ad may leave an empty box on a page rather than collapsing it.
Browsers that bypass your DNS. Chrome and Edge have their own Secure DNS setting that can override the device. Point it at your provider or turn it off.
Away from home. A router setting only works on your home network. Phones need their own setup to stay protected on cellular and public Wi-Fi.

DNS blocking also does not hide your traffic from your internet provider. For that you need a VPN. See Do You Need a VPN?.

Check That It Works

Load a page that is heavy with ads and trackers and see whether the ads are gone. For a clearer answer, use the Adblock Test, which checks whether known ad and tracker domains are being blocked on your connection.

Related guides: Change your router DNS, Stop targeted ads.

Common Questions

Do I need to install anything on each device?

Not if you set DNS on the router. Away from home, each phone or laptop needs its own DNS setting or profile.

Will it break websites?

Occasionally. A site or login can depend on a domain that is on a blocklist. A good service lets you allow a domain with one change.

Is DNS blocking as good as uBlock Origin?

Different strengths. A browser extension can hide page elements and remove in-page ads. DNS blocking covers every device and app but cannot touch ads served from the content's own domain. Using both is common.

Does it slow down browsing?

Usually the opposite. Blocked ads and trackers never load, so pages often load faster.

BLOCK ADS ON EVERYTHING AT HOME

Harbor Adblock is private DNS with ad and tracker blocking, from $1.99 a month with a 30-day free trial. See Harbor Adblock.