When you update a nameserver or DNS record, the change doesn't reach every device instantly. Your computer, your router, and even your browser keep a local copy of the old DNS answer for a while so they don't have to look it up again. That local copy is called a DNS cache, and it's usually why you're still seeing your old website or old email settings after making a change that should already be live elsewhere.
Clearing your own DNS cache won't speed up the change everywhere on the internet, but it will let you check sooner whether the update has actually gone through from your own computer.
Why You're Still Seeing the Old Site or Email
- Your computer's operating system cached the old DNS answer and hasn't asked again yet.
- Your browser keeps its own separate DNS cache, on top of the operating system's.
- Your router or your internet provider may also be caching the old answer.
Clearing the first two (your computer and your browser) is something you can do yourself in under a minute.
How to Clear Your DNS Cache on Windows
- Press the Windows key, type cmd, then right-click Command Prompt and choose Run as administrator.
- Type
ipconfig /flushdnsand press Enter. - You should see a message confirming the DNS resolver cache was successfully flushed.
How to Clear Your DNS Cache on macOS
- Open Terminal (from Applications > Utilities, or search for it with Spotlight).
- Type
sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponderand press Enter. - Enter your Mac's password when prompted (it won't be visible as you type) and press Enter again.
How to Clear the DNS Cache in Chrome
- Open a new tab and go to chrome://net-internals/#dns.
- Click Clear host cache.
- Close and reopen Chrome so the change takes effect.
Other browsers have similar built-in DNS caches; if you use a different browser, try a private/incognito window first, since it usually starts without any cached DNS entries.
Other Ways to Check If the Change Has Gone Through
- Switch your phone to mobile data instead of WiFi and open the site there. Mobile networks often pick up DNS changes faster since they're not using your home router's cache.
- Try a device on a completely different network, such as a friend's WiFi or a cybercafe.
- Use an online DNS lookup tool to check what answer is currently being returned for your domain from outside your own network.
Clearing your local cache only affects what your own device sees. The wider internet updates on its own schedule, and it can still take anywhere from a few minutes up to 24-48 hours for a change to be visible everywhere, even after your own cache is cleared.
If it's been longer than 48 hours and the change still isn't visible anywhere, double-check that the nameserver or DNS record was saved correctly before assuming it's just a caching delay. For more on typical wait times, see How Long Do DNS Changes Take to Propagate?