How to flush your DNS cache

DNS turns a name such as example.com into an address such as 203.0.113.42. Because the same names get looked up over and over, every layer between you and the internet remembers the answer for a while: your browser, your operating system, your router and the resolver your provider or a public service runs. Each cached answer carries a time-to-live (TTL), set by the domain's owner, after which it is thrown away and fetched fresh.

Flushing deletes the cached answers on your own device so that the next lookup goes out to the resolver again. It takes a fraction of a second, needs no reboot and deletes nothing else: no browsing history, no cookies, no saved passwords. The cases where it helps are specific: a website moved hosts and you still see the old server; a domain you just configured does not resolve; a typo or a crashed network earlier left a "name not found" answer cached (negative caching is real, and the usual reason a site "comes back" after a flush).

It does not help when the stale answer lives further along the chain. Your router and your resolver keep their own caches, and the only cure there is waiting out the TTL or, for the big public resolvers, asking them to purge. More on that at the end.

1. Right-click the Start button and choose Terminal. (Command Prompt or PowerShell works the same way.)
2. Type ipconfig /flushdns and press Enter.
3. Windows replies Successfully flushed the DNS Resolver Cache. That is the whole job.

In PowerShell, Clear-DnsClientCache does exactly the same thing; Microsoft documents the two as equivalent. To see what is in the cache before or after, run ipconfig /displaydns, which lists every cached record with its remaining TTL in seconds, including entries loaded from the hosts file. The command works in an ordinary window; if you ever see an access error, reopen it as Terminal (Admin).

If the problem is a stuck network rather than a stuck name, the companion commands are ipconfig /release followed by ipconfig /renew, which hand the computer's IP address back to the router and ask for a fresh one. Those two do need an administrator window, and the connection drops for a second or two while they run.

1. Open Terminal (press Cmd + Space, type Terminal, press Return).
2. Paste sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder and press Return.
3. Type your Mac login password when asked. The cursor does not move while you type; that is normal. Press Return again.

The command produces no output when it succeeds. The second half is the one that matters on every macOS release since 10.15 Catalina: mDNSResponder is the process that resolves and caches names, and the HUP signal tells it to drop its cache and keep running. The first half clears the older Directory Services cache, which costs nothing and covers machines still on an old release, so the one-liner is safe to use everywhere.

Safari has no DNS cache of its own; it uses the system's, so the command above is all a Safari user needs. Chrome and Firefox on a Mac keep their own, covered below.

Most desktop distributions released since 2020 (Ubuntu, Fedora, Debian 12, Arch) resolve names through systemd-resolved:

sudo resolvectl flush-caches

It prints nothing on success. resolvectl statistics shows the current cache size, so you can confirm it dropped to zero. On older systems the same command was spelled sudo systemd-resolve --flush-caches.

If your machine runs a different caching service, restart it instead:

• nscd:sudo systemctl restart nscd
• dnsmasq:sudo systemctl restart dnsmasq
• BIND (named):sudo rndc flush

Not sure which one you have? sudo lsof -i :53 lists whatever is listening on the DNS port. If nothing is, your Linux box has no system-level cache at all: every lookup already goes straight to the resolver in /etc/resolv.conf, and there is nothing to flush except the browser.

Chromium-based browsers cache DNS answers inside the browser, separately from the operating system, and a system flush does not touch them.

1. Open a new tab and go to chrome://net-internals/#dns (Edge: edge://net-internals/#dns; Brave: brave://net-internals/#dns).
2. Click Clear host cache. There is no confirmation message.
3. If the site still behaves oddly, go to chrome://net-internals/#sockets and click Flush socket pools, which closes the browser's open connections to the old server.

Firefox: open about:networking#dns and click Clear DNS Cache. Firefox's cache lives in memory only, so restarting the browser clears it too. The same net-internals page works in Chrome for Android, which is the only way to clear the browser's cache on a phone short of restarting it.

Neither mobile system exposes a flush command, but both drop their DNS cache when the network interface goes down and comes back.

1. Open the quick settings panel (swipe down from the top) and turn Airplane mode on.
2. Wait about ten seconds, then turn it off again. Wi-Fi and mobile data reconnect and start with an empty cache.

A restart does the same. On Android, Chrome's chrome://net-internals/#dns page clears the browser's own cache as well. On an iPhone the heavier option is Settings > General > Transfer or Reset iPhone > Reset > Reset Network Settings, which Apple notes also wipes saved Wi-Fi networks and passwords, cellular settings, and VPN and APN settings, so keep it for the day Airplane mode does not help. If you use an encrypted resolver through Private DNS on Android, switching it off and on again clears that cache too.

After a flush, the first visit to a site should get a fresh answer. To see what that answer is without opening the site, run the DNS lookup on the domain: it asks two independent resolvers and shows the A and AAAA records each one returns, with the TTL. If both agree with the new address but your browser still lands on the old server, the stale record is in the browser (clear it as above) or in the hosts file, which overrides DNS entirely: C:\Windows\System32\drivers\etc\hosts on Windows, /etc/hosts on macOS and Linux.

If the lookup itself still returns the old address, the cache is upstream. The What is my DNS server page shows which resolver answers your lookups. Rebooting the router clears its cache. The two largest public resolvers let anyone purge a domain: Google Public DNS flush and Cloudflare 1.1.1.1 purge both take a domain name and a record type. Your provider's resolver has no such button, and the only option there is to wait out the TTL or switch resolvers.

One last check: if you expected a VPN or an encrypted resolver to be answering and the lookup shows your ISP instead, run the DNS leak test. A cache does not cause that; a misrouted query does.