DNS Propagation Checker
Enter a domain and record type — optionally, the value you expect — and compare answers from several independent public DNS resolvers at once.
Different resolvers can show different cached values during a DNS change. Resolver agreement is a useful signal — it does not prove every DNS cache worldwide has updated.
Leave blank to compare resolvers against each other. Enter the value you expect (e.g. your new server IP) to check each resolver against it directly.
What is DNS Propagation?
DNS propagation refers to DNS changes becoming visible across the internet's recursive resolvers. It is not a single, synchronized rollout: each recursive resolver caches a record independently, for as long as that record's TTL (Time To Live) says, starting from whenever that resolver last looked the record up. Two resolvers can show different answers for the same query simply because their caches started their countdowns at different moments — that does not mean DNS is broken.
This tool queries the same DNS record from several independent public resolvers at once and shows you exactly what each one currently returns, so you can see whether they agree or are still showing different cached values.
Why Results Can Differ Between Resolvers
There is no single, universal DNS propagation timer. How quickly a change becomes visible depends on:
- TTL — how long a resolver is allowed to reuse a cached answer before it must ask again. A lower TTL means resolvers refresh sooner.
- When each resolver last queried the record — a resolver that cached the old value five minutes before your change will keep serving it until its own TTL runs out, even if another resolver that queried a moment later already sees the new value.
- Negative caching — an NXDOMAIN or empty answer can itself be cached for a period, which can briefly delay a newly-added record from appearing even after it exists at the authoritative nameservers.
- Nameserver/delegation changes — updating which nameservers are authoritative for a domain involves the parent zone and registry, and can behave differently from changing an individual record like an A or MX record.
Which Resolvers This Tool Checks
Every check queries three independent public DNS resolver services directly from our server:
- Google Public DNS
- Cloudflare DNS
- AdGuard DNS (Unfiltered) — the non-filtering resolver, so ad/tracker blocklists can't be mistaken for a DNS difference
This tells you whether several major independent resolvers currently agree — it does not prove that every resolver worldwide, or every internet service provider's own resolver, has updated. All three are large anycast services queried from wherever our server happens to be routed to at query time, not from a fixed set of geographic locations, so this tool does not claim to check DNS from specific countries or cities.
How to Read the Results
Without an expected value
Resolvers are grouped by what they currently show. If every resolver falls into one group, they agree. If resolvers split into more than one group — including a group that says NXDOMAIN, or a group with no record at all — that split is shown directly, resolver by resolver.
With an expected value
Each resolver is checked against the value you entered and marked as a match, a different value, no record, or NXDOMAIN. A resolver that timed out or returned an error is marked unavailable and is not counted toward the match total either way.
Related DNS Tools
🌐 DNS Records Checker
Look up all DNS record types for any domain from a single resolver.
📊 DNS Report Checker
DNS configuration health check with scores and recommendations.
🔄 Reverse NS Checker
Look up nameserver information.
🔍 HTTP Status Checker
Check HTTP response codes.
📖 Learn More About DNS Propagation
DNS Propagation Explained
How independent resolver caching actually works, how long changes really take, and how to check it.
DNS TTL Explained
The caching mechanic behind propagation — what TTL controls and how to use it deliberately.
📚 Frequently Asked Questions
Q: Why do the resolvers show different answers?
A: Each resolver caches independently based on TTL and when it last queried the record. A resolver that queried before your change will keep its cached answer until that TTL expires, regardless of what other resolvers already show.
Q: All resolvers agree — does that mean my change has fully propagated everywhere?
A: It means the resolvers this tool checks currently agree. It does not prove every resolver worldwide — including your own ISP's resolver or a corporate/local cache — has refreshed. Those can still be serving an older cached value until their own TTL runs out.
Q: What does the Expected Value field do?
A: It lets you check each resolver directly against a specific value you supply (for example, your new server's IP address) instead of just comparing resolvers to each other. Each resolver is then marked as a match, a different value, no record, or NXDOMAIN.
Q: A resolver shows "Unavailable" — does that count as a mismatch?
A: No. A timeout, HTTP error, or SERVFAIL from a resolver means that resolver didn't answer — it is excluded from the match count and shown separately, not treated as evidence the record is missing.
Q: What's the difference between NXDOMAIN and "no record"?
A: NXDOMAIN means the resolver believes the domain itself doesn't exist. "No record" (empty NOERROR) means the domain exists but has no record of the type you selected. This tool always shows them separately.
Q: Which DNS resolvers does this tool query?
A: Google Public DNS, Cloudflare DNS, and AdGuard DNS's unfiltered resolver — see "Which Resolvers This Tool Checks" above for details.
Q: Is this DNS propagation checker free?
A: Yes, free with no registration required. Usage is rate-limited per visitor to keep the tool available for everyone.
Privacy
The domain and record type you enter are sent to the public DNS resolver providers shown in the results above (Google, Cloudflare, and AdGuard) in order to look up the record. Checks are not stored server-side or logged against you.