How to flush DNS on Windows, Mac and Linux

Flushing DNS clears the website addresses your computer has remembered, so it looks them up fresh. The command depends on what you're using:

Windows (Command Prompt)   ipconfig /flushdns
Windows (PowerShell)       Clear-DnsClientCache
macOS                      sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder
Linux (systemd)            sudo resolvectl flush-caches

They all work straight away, and you don't need to restart. If that fixed it, you're done. If not, your browser or phone probably has its own cache too, and that's covered further down.

What flushing DNS actually does

When you visit a website, your computer has to turn a name like example.com into an IP address. It doesn't ask a DNS server every single time. It remembers the answers for a while, in what's called the DNS cache.

Most of the time that's exactly what you want. Microsoft describes it as what lets Windows "resolve frequently queried names quickly, before querying its configured DNS servers."

It becomes a problem when one of those remembered answers goes stale. A site moves to a new server and your computer keeps sending you to the old one. Flushing throws the remembered answers out, so the next lookup goes back to a DNS server and gets the current address.

There's a less obvious case too, and it trips people up. The cache doesn't just store lookups that worked, it stores ones that failed. Microsoft's documentation for ipconfig says flushing lets you "discard negative cache entries", which is the proper name for a cached "this domain doesn't exist" answer. So if you checked a domain before its DNS was set up, your computer can go on insisting it doesn't exist long after it does. Flushing gets rid of that.

How to flush DNS on Windows 11 and Windows 10

It's the same command on both.

Using Command Prompt

1. Press the Windows key and type cmd
2. Click Command Prompt
3. Type this and press Enter:

ipconfig /flushdns

Windows prints a short message confirming the DNS resolver cache was flushed. If you get an access denied error instead, close the window, right click Command Prompt, pick Run as administrator and try again.

Using PowerShell

If you'd rather use PowerShell, run:

Clear-DnsClientCache

Microsoft documents this cmdlet as "equivalent to running ipconfig /flushdns", so use whichever you already have open.

Checking what's in the cache first

You can see what Windows has remembered before you clear it:

ipconfig /displaydns

Or Get-DnsClientCache in PowerShell.

There's a useful detail buried in Microsoft's ipconfig reference: the cache includes entries "preloaded from the local Hosts file" as well as normal lookups. So if you've edited your hosts file and want to know whether Windows has noticed, /displaydns will tell you. Flushing won't change anything in the hosts file itself, mind. If you need to edit that, the Windows hosts file guide covers where it lives and why Windows so often refuses to save it.

How to flush DNS on Mac

Open Terminal. You'll find it in Applications, then Utilities, or press Command and Space and type terminal. Then run:

sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder

Enter your Mac login password when it asks, and press Return. You won't see the password as you type, which is normal.

Nothing gets printed when it works, and that catches a lot of people out. macOS doesn't show a confirmation message at all, so if you're simply dropped back at the prompt, it worked.

You do need both parts of that command. The first clears the directory services cache, and the second tells mDNSResponder, the process macOS uses for DNS, to reload. Run only one and part of the cache can survive.

The same command works on macOS Ventura, Sonoma, Sequoia and macOS 26 Tahoe.

How to flush DNS on Linux

Linux is the awkward one, because the answer depends on how your system is set up, and there may be nothing to flush at all.

Plenty of Linux installs don't keep a local DNS cache. You'll only have one to clear if you're running a caching service like systemd-resolved, nscd or dnsmasq.

Ubuntu, Debian and other systemd distributions

On current releases, including Ubuntu 22.04, Ubuntu 24.04 and Debian Bookworm:

sudo resolvectl flush-caches

Older guides tell you to run sudo systemd-resolve --flush-caches. That command was renamed to resolvectl in systemd version 239, and the old name is deprecated. On newer distributions it just throws an error.

If you use nscd

sudo systemctl restart nscd

If you use dnsmasq

sudo systemctl restart dnsmasq

How to clear the DNS cache in your browser

Chrome and Firefox each keep a DNS cache of their own, completely separate from your operating system. You can flush Windows or macOS perfectly and still get the old site in your browser, which is usually when people conclude flushing doesn't work.

Chrome

1. Type chrome://net-internals/#dns into the address bar and press Enter
2. Click Clear host cache

There's no confirmation, it just clears. If a page still loads from the old server after that, Chrome may be reusing a connection it already had open. Go to chrome://net-internals/#sockets and click Flush socket pools to close them.

Firefox

1. Type about:networking#dns into the address bar and press Enter
2. Click Clear DNS Cache

Mozilla added that button in bug 1593476. If you've got DNS over HTTPS turned on in Firefox, it resolves names inside the browser instead of going through your operating system, which is one more reason to clear it here.

How to flush DNS on iPhone and Android

Neither phone gives you a flush DNS button.

On an iPhone, open Settings, switch Airplane Mode on, then switch it off again. Restarting the phone does the same job.

Android has no system option for it. Open Chrome, go to chrome://net-internals/#dns and tap Clear host cache. That clears the browser's cache, which is usually the one causing trouble anyway.

When flushing DNS helps, and when it won't

Flushing fixes things on your own device. It's the right thing to try when:

• A site you use has moved to a new server and your computer keeps loading the old one
• A domain that didn't exist a few minutes ago does now, but your computer still says it can't be found
• You've edited your hosts file and the change isn't taking effect
• The site works on someone else's device but not yours

It won't help when the stale answer lives somewhere other than your computer. Your router, your internet provider's DNS servers and the TTL on the DNS record all hold copies you can't reach from your keyboard. If you've just changed a DNS record and the new server still isn't showing, that wait is controlled by the TTL that was on the record before you changed it. How long DNS propagation really takes goes into which part of that you can actually influence.

It's also why flushing is a poor way to test a site you're moving. You'd be waiting on caches all over the internet, not only yours. It's much quicker to check the new server directly before you touch DNS at all. DNS Previewer gives you a link that loads your site from the new server under its real domain name, so you can make sure everything works and then change the record. It's free, and the link opens on any device, phones included, without flushing a thing.