When you change your NS addresses or DNS records, it takes a while for the change to be visible everywhere on the internet. This process is called DNS propagation.
Why isn't it instant?
Internet service providers and your own computer keep DNS answers in a cache for a while. This period is called the TTL (Time To Live). Until the cached record expires, the old address keeps being used.
| Change | Estimated time |
|---|---|
| NS address change | A few hours, at most 24 – 48 hours |
| A, CNAME, MX, TXT record change | From a few minutes to a few hours, depending on TTL |
What happens in the meantime?
Some visitors may see the new version of your website and some the old one. Email may briefly arrive at the old server. This is temporary and resolves itself when propagation is complete.
Can I speed it up on my own computer?
- Clear the DNS cache. On Windows run
ipconfig /flushdnsin Command Prompt; on a Mac runsudo dscacheutil -flushcache; sudo killall -HUP mDNSResponderin Terminal. - Clear your browser cache or open the page in a private window.
- Restart your modem.
If you are planning a move, lowering the TTL to 300 seconds a day before the change shortens propagation.
How do I check propagation?
Enter your domain on dnschecker.org or whatsmydns.net to see which address is returned in different parts of the world. The command nslookup yourdomain.com also works.
