How to change your DNS server on a computer, phone or router

Your device normally uses the DNS resolver your internet provider hands out. Usually that is fine, but if lookups are slow, some names fail to resolve or a stale answer will not clear, switching to a public resolver is a quick and reversible fix. This guide shows how, and how to put things back.

Before you change anything

Note the current settings, or take a screenshot, so you can restore them.
A DNS change affects name lookups only. It does not change your speed or your connection, though faster lookups can make pages start sooner.
Public resolvers are run by companies who can, depending on their policies, see the names you look up. Read the provider’s privacy statement if that matters to you.

Commonly used public resolvers

Cloudflare: 1.1.1.1 and 1.0.0.1
Google: 8.8.8.8 and 8.8.4.4
Quad9: 9.9.9.9 and 149.112.112.112, which also blocks known malicious sites

Always enter a primary and a secondary address, so lookups continue if one is unreachable.

Windows 11

Open Settings, then Network & internet.
Choose Wi-Fi or Ethernet, then open the properties of your connection.
Next to DNS server assignment, choose Edit and switch from automatic to Manual.
Turn on IPv4, enter the preferred and alternate addresses, and save.

To undo, choose Edit again and set it back to Automatic (DHCP).

Mac

Open System Settings, then Network.
Select your connection and click Details.
Choose DNS, press the plus button and add the addresses.
Remove any old entries you want to replace, then click OK.

To undo, remove the entries you added and the Mac goes back to using what the network provides.

iPhone and iPad

Open Settings and tap Wi-Fi.
Tap the information icon next to your network.
Choose Configure DNS and switch to Manual.
Remove existing servers, add the new ones and save.

This applies to that one Wi-Fi network only. It does not change mobile data. To undo, set Configure DNS back to Automatic.

Android

Recent versions of Android have a Private DNS setting, usually under Settings, Network & internet. Choose the private DNS provider hostname option and enter a provider’s hostname, such as one.one.one.one for Cloudflare or dns.google for Google. Unlike the per-network setting above, this works on both Wi-Fi and mobile data. To undo, set it back to Automatic or Off. Menu names vary by manufacturer, so use the search box in Settings if you cannot find it.

On your home router

Changing it on the router applies to every device at home. Log in to the router’s settings page, using the address and login printed on its label, and look for DNS, usually under internet or WAN settings. Enter the primary and secondary addresses and save. The router may restart. Some provider-supplied routers do not allow this change, in which case change it on individual devices instead.

After you change it

Flush your device’s cache so it forgets old answers. See how to flush your DNS cache.
Restart your browser.
Try the site that was failing, or run it through our website checker.

Checking it worked

Our DNS lookup tool shows what a name resolves to from our servers, so you can compare it with what your own device gets. If your device returns a different or missing answer, the cache or the resolver is the cause.

If it did not help

The site may genuinely be down. Check from elsewhere with our tool.
A VPN or security app may be overriding your DNS settings.
Some networks, such as workplaces and schools, force their own resolver and block others.
If the name is unknown everywhere, the problem is the site’s own DNS. See what DNS_PROBE_FINISHED_NXDOMAIN means.

If a public resolver makes no difference, put your settings back to automatic. There is no benefit in keeping a change that does nothing.

Check a website now

Is it down for everyone, or just you? Paste an address and we test it from fifteen places.

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Last updated 2 November 2026. Written by the siteupdown.com team. Spotted a mistake?

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