Free tool / Propagation watch
Is your change live yet?
After you publish a record, resolvers pick it up at different times. Watch four of the largest public ones update, live, and see how long caches may keep the old value.
Why changes take time
Caches, not the internet
Your DNS host updates instantly. Resolvers that asked before your change keep the old answer until its TTL (time to live) runs out, often five minutes to an hour.
“Up to 48 hours” is the worst case
Long waits mostly come from records that had a very long TTL, or from changing name servers. A new TXT record that didn’t exist before is usually visible within minutes.