DNS Tools
DNS Propagation Checker
See whether your DNS change has reached the major public resolvers yet.
How it works
The tool first asks the domain's own name servers for the current record. That's the source of truth. It then asks a dozen public resolvers the same question at the same time. Resolvers that return the same answer are marked updated. Resolvers that return something else are most likely still holding an older cached copy.
FAQ
- What is DNS propagation?
- When you change a DNS record, resolvers around the world that already cached the old answer keep using it until its TTL (time to live) runs out. "Propagation" is just those caches expiring one by one and fetching the new answer. Nothing is actively pushed out.
- How long does propagation take?
- Usually minutes to a few hours, depending on the record's TTL. If the old record had a TTL of 86400 seconds (24 hours), some resolvers can hold the old answer for up to a day. Lowering the TTL a day before a planned change makes the switch much faster.
- What does "Old / different" mean?
- That resolver returned something other than what the domain's own (authoritative) name servers say right now. Most often it's still serving a cached old answer. It will update on its own when its cache expires.
- Why do big sites show different IPs even with no recent change?
- Large sites (GitHub, Google, CDNs) use geo-aware DNS: they deliberately hand out different IP addresses depending on which resolver asks, to send visitors to a nearby server. For those, "different" is normal and not a propagation problem.
- Are these queries sent from each country?
- No. Every query is sent from the RouteLearn server to each provider. "Based in" is where the provider is based, and most of them run global anycast networks. What this shows is whether each provider's cache has your change yet, which is usually what you want to know.