DNS propagation checker
Ask 12 public resolvers for the same record at once and see which of them agree. Watch a DNS change spread, and find the caches still serving the old answer.
Related tools: DNS lookup · A record lookup · CNAME lookup · NS lookup · TXT record lookup · CAA record lookup · Reverse DNS lookup · All free tools
The same question, asked of many caches
DNS propagation is the time it takes for a changed record to reach every resolver that cached the old one; there is no central switch, only caches expiring at their own pace. This tool sends one query for the record type you choose to 12 public resolvers (Cloudflare, Google, Quad9, OpenDNS, AdGuard, Mullvad, Control D, NextDNS, DNS.SB, AliDNS, IIJ, SWITCH) in parallel over DNS-over-HTTPS, then compares the answers and marks each one as matching the majority or not.
Once the change has propagated, the question becomes whether it stays put. Records get edited by mistake and zones get hijacked, and Upcheck re-resolves every website every 6 hours and alerts your team when a record changes.
Three steps, no signup
- 01
Enter a name and pick a record type
The name you changed, and the type you changed: A for an address, CNAME for an alias, MX for mail, NS for a nameserver move.
- 02
We query 12 resolvers in parallel
Each public resolver is asked the same question at the same moment, from Cloudflare's network, over DNS-over-HTTPS.
- 03
Answers are compared
The majority answer is the baseline; every resolver is marked as agreeing or differing, with its own answer shown in full.
Frequently asked questions
How long does DNS propagation take?
As long as the old record's TTL, plus however long the change takes to reach your authoritative nameservers. A resolver that cached the old answer keeps it until that TTL expires, then fetches the new one; a resolver that never cached it sees the change immediately. With a TTL of 300 seconds, most of the internet follows within minutes. With the 48-hour TTLs common on nameserver delegations, it can take two days. Lowering the TTL a day before a planned change shortens the wait.
Some resolvers show the new answer and some the old. Is something wrong?
No, that is propagation in progress. Each resolver's cache expires on its own schedule, so for a while they disagree. Check again as the old TTL runs out. If the split persists well past the TTL, look at whether every one of your authoritative nameservers is serving the new record: a resolver that happens to ask a stale nameserver keeps getting the old answer.
Does this check propagation in different countries?
Not by geography. Each of these resolvers is anycast, so the query lands at whichever of its sites is nearest to where this check runs. What differs between them is their caches, which is what propagation is about. A resolver in a particular country can still hold a stale answer; the picture here is across providers, not across map locations.
The resolvers agree except one, which returns different addresses. Why?
If the name is served by a CDN or a proxy such as Cloudflare, the addresses it returns can legitimately differ by where the query was answered: each resolver's nearest site may hand out a different pool. That is not a propagation problem. Compare the answers themselves: addresses from the same provider's ranges mean the record is consistent, while an address from an old host means that resolver is still serving the previous record.
Why does one resolver return an error or no answer?
Public resolvers rate-limit and occasionally time out, and a few refuse queries for certain names. A single resolver failing while the others agree tells you nothing about your record. If all of them fail, the name is likely not delegated, or your authoritative nameservers aren't answering.
Is this DNS propagation checker free?
Yes. No account, and no limit on checks by hand; scripted use is rate limited because each check fans out to a dozen resolvers. Upcheck's paid monitoring watches the records for every website you add, every 6 hours, and alerts your team when one changes.
Propagation is the change spreading. Monitoring is knowing when it changes again.
Add your websites to Upcheck and get alerted by email, Slack, Discord, Teams, or webhook when a DNS record moves.