Queries Cloudflare, Google, Quad9, AliDNS and DNS.SB. Ideal after changing an SPF / DMARC / MX / A record.
Why a DNS change isn’t instant
The moment you save a DNS change, only your own nameservers have the new value. Every other resolver on the internet keeps serving the old one from cache until the record’s TTL expires. That’s why a new website, a migrated mailbox or an updated SPF record can work for you and not yet for a colleague across the country.
Caches hold the old value until the TTL expires — then resolvers refetch and converge.
The TTL is the lever
Propagation time is mostly the record’s TTL. A 300-second TTL clears in minutes; a 24-hour TTL means caches can serve the old value for a full day. The professional move before any planned change is to lower the TTL a day ahead, make the change, confirm it here, then restore a normal TTL. You can’t force someone else’s resolver to flush, but a low pre-change TTL gives you the fastest clean cut-over.
Reading the results
Green ticks across all resolvers mean the change is live everywhere they reach. A mix means it’s still propagating — wait for the TTL — or, for A records behind a CDN, that different locations legitimately get different IPs. A resolver marked “no response” simply didn’t answer in time and isn’t a sign of trouble. For a complete record dump from one resolver, switch to the DNS Lookup tool.
Most useful after an email change
This tool pairs naturally with the email work above: publish a new SPF or DMARC record, then check the TXT here to confirm the world can see it before you rely on it. Pair it with the SPF, DMARC and DKIM checkers.
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DNS propagation — common questions
What is DNS propagation?
When you change a DNS record, resolvers around the world don’t all see it instantly. They keep serving the previous value from cache until the record’s TTL (time-to-live) expires, then fetch the new one. “Propagation” is that period while different resolvers may return different answers.
How long does DNS propagation take?
Usually minutes to a few hours, governed mainly by the record’s TTL — a 300-second TTL clears far faster than an 86,400-second (24-hour) one. Nameserver (NS) and registrar changes can take longer. Lowering the TTL a day before a planned change makes the switch propagate quickly.
How do I use this checker?
Enter the host or domain, pick the record type (A, AAAA, MX, TXT, CNAME or NS) and check. The tool queries several major public resolvers in different networks and shows whether they all return the same value yet — ideal right after changing an SPF, DMARC, MX or A record.
Which resolvers does it query?
It queries the public DNS-over-HTTPS resolvers run by Cloudflare, Google, Quad9, AliDNS and DNS.SB — independent operators across different regions. That spread is enough to confirm whether a change has reached the wider internet, without relying on any single provider.
Why do some resolvers show a different answer?
Two normal reasons: the change hasn’t propagated everywhere yet (some still hold the cached value until TTL expiry), or the record is a CDN/load-balanced A record that legitimately returns different IPs by location. A resolver shown as “no response” simply didn’t answer in time — it isn’t a propagation failure.
How can I make changes propagate faster?
Lower the record’s TTL well before you change it (so caches expire quickly), make the change, confirm with this checker, then raise the TTL back up. You can’t force third-party resolvers to flush early, but a low pre-change TTL gives you the fastest practical switch.
Does this replace a full DNS lookup?
It’s focused on comparing one record across resolvers. To see every record for a domain (A, AAAA, MX, NS, TXT, CNAME) from one resolver, use our DNS Lookup tool instead.