Free DNS tool
DNS Checker
Look up the records for a domain across major public DNS resolvers at once, and see whether a recent change has finished propagating.
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Compares the public resolvers Google, Cloudflare, DNS.SB and AliDNS over DNS-over-HTTPS, in your browser. They cache independently, so differences usually mean a record is still propagating (large CDN or geo-routed sites can differ by design).
A change is only live once it propagates everywhere. Pulsetic monitors your domain and SSL certificate from multiple regions around the clock.
What is DNS propagation?
When you change a DNS record, the new value does not reach the whole internet at once. Resolvers around the world cache the previous value for the length of its TTL, and only fetch the new one after that timer expires. During that window the same name can resolve differently depending on which resolver answers. That window is DNS propagation.
This DNS checker makes the window visible. It asks several major public resolvers for the same record at the same time and lines up their answers, so you can see at a glance whether a change has reached them all or is still rolling out.
Why resolvers disagree
Every resolver keeps its own cache. The moment one of them fetches your new record, it serves the new value until the TTL expires; a resolver that cached the old value a minute earlier keeps serving the old one for the rest of that TTL. With independent caches across different operators, a mid-propagation record shows up as a split: some resolvers on the new value, some on the old.
Name server (NS) changes are the slowest, because the delegation is cached at the top-level domain and by every resolver below it, often for up to 48 hours. Address records usually settle within their TTL, commonly an hour or less.
How to speed up a DNS change
You cannot force a resolver to drop a cached record early, but you can plan ahead. A day or two before a planned change, lower the record TTL to a small value such as 300 seconds. Resolvers then cache the old value for only five minutes, so when you make the switch it propagates almost immediately. Once the change has settled, raise the TTL again to reduce lookup load.
After a migration, confirm the new value here, then run a normal DNS lookup and an outside is-it-down check to be sure the server behind the record is actually serving traffic.
Frequently asked questions
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What is DNS propagation?
DNS propagation is the time it takes for a change to your DNS records to reach resolvers everywhere. Each resolver caches the old value for the length of its TTL, so a change appears at different times depending on who is asking.
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How long does DNS propagation take?
Anywhere from a few minutes to about 48 hours. The main factor is the TTL on the record before you changed it; resolvers keep serving the cached value until that TTL expires. Name server (NS) changes can take the longest.
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Why do different resolvers show different results?
Because each resolver caches independently. During propagation some resolvers still hold the old record while others have already fetched the new one. This checker queries several public resolvers at once so you can see that split directly.
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How do I check if my DNS has propagated?
Enter your domain above and pick the record type. When every resolver returns the same value, the change has propagated for those resolvers; while they disagree, it is still rolling out.
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How can I make DNS changes propagate faster?
Lower the record TTL a day or two before a planned change, so resolvers cache the old value for a shorter time. After the change has settled, you can raise the TTL again.
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Is this a geographic propagation map?
No. It compares major public resolvers (Google, Cloudflare, DNS.SB and AliDNS), which run on global anycast networks and cache independently. That reveals propagation lag between operators, though it is not a city-by-city map.
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Why does a large site show as out of sync?
Some sites, especially those behind a CDN, deliberately return different addresses to different resolvers by region. That shows here as out of sync even though nothing is propagating. For your own records, which usually resolve to a single address, a split does mean a change is still rolling out.
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Know the moment a DNS or domain change breaks something
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