Network Tools
DNS Propagation Checker
Check how DNS results differ across multiple public DNS resolvers.
DNS propagation check
What is DNS propagation?
"Propagation" is a slightly misleading word. Nothing is pushed anywhere when you change a DNS record. You edit the record at your authoritative nameserver, and that change is visible immediately to anyone who asks that nameserver directly. What takes time is the expiry of cached copies already held by resolvers around the world.
Every resolver that looked up your record before the change kept a copy for the length of its TTL. Until that copy expires, that resolver keeps handing out the old answer. Propagation is really just the sum of every cache expiring at its own pace.
Why do DNS results differ between resolvers?
- Different cache ages. Each resolver cached your record at a different moment, so each has a different amount of TTL left.
- Independent infrastructure. Large resolvers run many nodes that do not share one cache, so even the same provider can answer differently from different places.
- Filtering policies. Some resolvers deliberately block malware or ad domains, returning a sinkhole address or nothing at all.
- Negative caching. If a name did not exist when a resolver last asked, it caches that absence too — governed by the zone's SOA minimum TTL.
What does TTL mean?
TTL — time to live — is how many seconds a resolver may reuse a cached answer before asking again. The value shown for each resolver above is the time remaining on its copy, not the TTL you configured, which is why the numbers differ even when the answer is identical. A low remaining TTL means that resolver is about to refresh.
TTL is a permission, not a promise. A resolver may refresh sooner, and some ignore very small values. Do not treat a countdown as a guarantee of when a change will be complete.
How long does a DNS change take?
It depends almost entirely on the TTL of the old record, because that is what determines when caches let go of it. With a 300-second TTL most resolvers pick up a change within minutes. With a 86,400-second TTL some will not refresh for a day.
The familiar "DNS takes 24 to 48 hours" advice comes from an era of much longer default TTLs and is rarely accurate now. If you know a change is coming, lower the TTL well in advance — at least one full old-TTL period — then make the change, then raise it again.
What does "consistent across tested resolvers" mean?
It means every resolver we queried returned the same records at the moment you ran the check. That is a genuine, useful signal: these are independently operated resolvers with separate caches, so agreement between them suggests the change has been picked up broadly.
It is not proof that the change is visible everywhere. All of our queries leave from one server, and public resolvers are anycast — the Cloudflare node answering us is not the one answering a user in São Paulo. Treat a consistent result as strong evidence, not as a worldwide guarantee.
Which resolvers are tested?
Cloudflare, Google Public DNS, Quad9 and Control D. They are labelled by provider rather than by country, because all of them are anycast networks with nodes in many places — claiming a specific country for an answer would be invented detail.
Some widely-known resolvers are deliberately absent. OpenDNS refuses recursive queries from datacentre address ranges, so it cannot be queried from a server like ours at all. Ad-blocking resolvers are excluded because they replace answers for advertising and analytics domains with a sinkhole address, which would show up here as a permanent disagreement that has nothing to do with propagation.
For a single detailed lookup of every record type, use the DNS Checker.
Frequently asked questions
What does this tool actually check?
It asks several large public DNS resolvers the same question from IPGet’s server and compares their answers. That tells you whether independent resolvers are serving the same record yet, and how stale each one’s cache is. It does not query resolvers in other countries, so it is not a worldwide propagation map.
Why do two resolvers show different results?
Because each resolver caches an answer for the length of its TTL, and they started caching at different moments. After you change a record, a resolver keeps serving the old value until its copy expires. Differences shortly after a change are normal and usually resolve themselves.
Does "consistent" mean my DNS change is finished everywhere?
No. It means every resolver we tested agreed at the moment you ran the check. Other resolvers, and the same providers reached from other parts of the world, may still hold an older cached copy until their TTL expires.
How long does a DNS change take?
It depends on the TTL of the record you changed, not on a fixed period. If the old record had a TTL of 300 seconds, most resolvers refresh within five minutes of their cached copy expiring. The common claim that DNS always takes 24 to 48 hours dates from an era of much longer TTLs and is rarely true today.
Why is one resolver marked as filtering?
Some public resolvers deliberately block categories of domains, such as known malware hosts. If a filtering resolver disagrees with the others, the cause may be a policy block rather than a stale cache, so the tool labels those resolvers rather than silently counting them as a difference.