How to use it
- Choose your device in the picker.
- Run the command or follow the steps shown.
- Close and reopen your browser.
- Open the site again. If it still fails, run the live check to see whether the site is down.
What flushing DNS does
Every time you open a site, your device asks a DNS server for the IP address behind the name, a number such as 203.0.113.7 behind example.com. To save time, it remembers the answer for a while. The site decides how long, using a value called TTL. Usually that is minutes to a few hours.
Trouble starts when the stored answer is wrong. A site that moved to a new server, a domain that was just set up, or a failed lookup that your device remembered as "does not exist" can keep failing on your device only, while it works for everyone else. A flush throws the stored answers away. It does not touch your files, passwords or history.
Why you may need to flush more than one cache
DNS answers are cached in several places. There is the operating system, which is what ipconfig /flushdns clears. There is the browser, which has its own list. Your router keeps one, and your provider's DNS server keeps another. If you flush the system and the site still fails, clear the browser host cache, then restart the router. The router flush is just a restart: unplug it for thirty seconds. You cannot flush your provider's cache yourself, but you can switch to a public DNS resolver in the network settings of your device or router, which skips it.
Check the result
On Windows you can see the stored names before and after with ipconfig /displaydns. According to Microsoft, /flushdns flushes and resets the contents of the DNS client resolver cache and is meant for DNS troubleshooting. After flushing, the list is empty and fills up again as you browse. To test a single name against a public resolver, run nslookup example.com 8.8.8.8. If that returns an address and your normal lookup does not, the problem is your DNS server, and switching it is the better fix.
Changing the DNS server as a lasting fix
If you flush often because the same sites keep failing, the DNS server your provider hands out may be unreliable. You can set a different one for a single device or for the whole router. Public resolvers such as Google Public DNS (8.8.8.8) and Cloudflare (1.1.1.1) are common choices. Change one thing at a time, note the old values before you overwrite them and test a few sites afterwards. A work or school network may require its own DNS server for internal addresses, so do not change settings on devices you do not own.
When flushing DNS will not help
If the site is down for everybody, no local change helps, so confirm that first with the website down checker. A flush also does nothing for blocked sites, expired certificates, a failing VPN or a firewall rule. For those, go through the full troubleshooting guide. Sources: Microsoft Learn, ipconfig command reference, and the resolvectl manual page. Checked on 25 October 2026.
Frequently asked questions
What does flushing DNS do?
It deletes the website addresses your device has stored from earlier lookups. The next visit asks the DNS server again, so a site that moved to a new server is found at its new address. Flushing never deletes your files, passwords or browsing history.
Is it safe to flush DNS?
Yes. The only effect is that the first visit to each site after the flush is a little slower while the addresses are looked up again.
How do I flush DNS on an iPhone?
There is no command. Turn on Airplane Mode for ten seconds and turn it off, or restart the phone. Both clear the cached lookups. Changing the Wi-Fi network also forces new lookups.
How do I flush DNS on Android?
Android has no flush command either. Toggle Airplane Mode, restart the phone, and clear the cache of the browser that has the problem in Settings, Apps, the browser, Storage.
Do I need to restart after flushing DNS?
Not on Windows or macOS. Browsers keep their own cache, so close and reopen the browser or clear its host cache as well.
Will flushing DNS fix a site that is down?
No. It only helps when the cause is an outdated address on your device. If the site itself is down, use the live checker to confirm that.