Understand DNS propagation

Why a change is instant for you and hours away for someone else, and how to check what the world sees.

Propagation is not one event. Each resolver on the internet holds its own cached copy of your records and keeps it until that copy expires. There is no way to force every resolver to refresh.

What decides the wait

• The TTL on the old record. This is the main factor. A record with a TTL of 3600 can be served from cache for another hour after you change it.
• Nameserver delegation. Changing nameservers is a registry change with its own TTL, commonly 24 or 48 hours.
• Your own machine. Operating systems, browsers and VPNs cache separately from your resolver.

Check what is live

# what your resolver has
dig +short example.com

# ask an authoritative nameserver directly
dig +short example.com @ns1.webvuecloud.com

# ask a public resolver
dig +short example.com @1.1.1.1

If the authoritative answer is right and a public resolver is wrong, the change is correct and you are waiting on cache. If the authoritative answer is wrong, the record is wrong.

Clear your own cache

# macOS
sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder

# Windows
ipconfig /flushdns