DNS Propagation Checker
Check whether a DNS change has reached public resolvers around the world, including Indian anycast nodes, and compare each answer with the zone's authoritative nameserver. Supports A, AAAA, CNAME, MX, NS, TXT, SOA and PTR records.
How DNS propagation works
When you change a record at your DNS provider, the authoritative nameservers answer with the new value immediately. Recursive resolvers run by ISPs and public DNS operators, however, keep the previous answer in cache until its TTL (time to live) expires. This checker queries 18 recursive resolvers in parallel with a 2 second timeout each and marks every one that already returns the same record set as the authoritative server as propagated.
Tip: before migrating a website or mail server to a new cloud server, lower the TTL to 300 seconds at least 24 hours in advance, then raise it again after the move.
Frequently asked questions
How long does DNS propagation take?
Usually minutes to a few hours; worst case up to 48 hours. The limiting factor is the TTL of the old record cached by each resolver. Lower the TTL a day before you plan a change.
Why do some resolvers show the old value?
They still hold the previous record in cache until its TTL expires. Resolvers that never cached the record return the new value immediately.
Which resolvers are checked?
18 public resolvers: Google, Cloudflare, Quad9, OpenDNS, Level3, Comodo, CleanBrowsing, AdGuard, Yandex, Hurricane Electric, plus region-labelled anycast nodes for India, Singapore, Germany, Australia, Brazil, Japan and the USA, and the authoritative nameserver of the zone.
What does propagated X/Y mean?
X of the Y resolvers returned exactly the same record set as the authoritative nameserver. When a resolver disagrees it is shown in amber.
Is there an API?
Yes: POST /tools/api/v1/dns/propagation with JSON {"name": "example.com", "type": "A"}. Rate limit is 30 requests per minute per IP.
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