What is DNS propagation?

When you change a DNS record or switch nameservers, the update does not appear everywhere at once: resolvers worldwide keep serving their cached copies until each TTL expires. This spread is called propagation and typically finishes within a few hours, though it can take up to 24–48 hours in slow corners of the internet. During propagation some visitors see the old site and some see the new one — that is expected, not a fault. Our DNS lookup tool queries live records so you can watch the change land.