DNS Propagation Checker
Compare how DNS records appear across major public resolvers worldwide.
What this tool does
This tool compares DNS answers from multiple resolvers so you can see whether a change has propagated globally. It highlights differences in record values, status codes, and availability across providers. Use it after updates to DNS records to confirm what users in different networks are likely to see.
Inputs explained
- Domain: The domain or hostname you want to check.
- Record type: The DNS record type to compare (A, AAAA, MX, NS, TXT, CNAME).
How it works / Method
The tool sends the same DNS query to a set of public recursive resolvers using DNS over HTTPS. It then displays each resolver's result side by side. Because resolvers cache data based on TTL values, results may differ until caches expire. This view reflects real-world resolution rather than a single authoritative server response.
| Resolver / Location | Result | Status |
|---|
Example
Input: Domain: example.com, Record type: A. Expected output: A table listing each resolver and its returned IPv4 address value(s). During a change, some resolvers may show the old address while others show the new address until TTLs expire.
Use cases
- Verify DNS changes after a hosting migration.
- Confirm new MX or TXT records for email setup.
- Troubleshoot regional access issues for a domain.
- Validate that nameserver changes are taking effect.
- Monitor propagation during incident response or recovery.
Limitations & notes
- Only the listed resolvers are checked, not every ISP or region.
- Results depend on resolver cache and TTL values and can be temporarily inconsistent.
- This tool does not bypass caches or query authoritative nameservers directly.
- Temporary resolver errors (SERVFAIL, timeout) can appear even when DNS is correct.
Accuracy & Disclaimer
Propagation results reflect public resolver caches at the time of the query. For authoritative results, confirm with your DNS provider or authoritative nameservers.
Frequently Asked Questions
How long does DNS propagation take?
Propagation time depends on TTL values and resolver caching. Some changes appear within minutes, while others can take many hours. Negative caching can delay visibility when a record was previously missing. Public resolvers also refresh at different times, so you may see mixed results. A common planning window is up to 24 to 48 hours, but well-managed changes with low TTLs often settle much faster.
Why do some resolvers still show old values?
Resolvers cache DNS answers until the TTL expires. If a resolver cached the old record just before your change, it will keep serving that value until the TTL window ends. Some networks also use forwarding or shared caches, which can extend the apparent delay. This is normal DNS behavior and is not an error. The mixed results are a signal that propagation is still in progress.
Does this tool query authoritative nameservers?
This tool queries public recursive resolvers, which may return cached results. It does not force direct queries to the authoritative nameservers for the zone. If you need the authoritative source of truth, use a DNS lookup against the domain's nameservers or consult your DNS provider. The propagation view is still valuable because it reflects what users and applications are likely to see.
Can I speed up propagation after a change?
You cannot purge caches across the internet, but you can plan changes by lowering TTL values in advance. Set a shorter TTL a day before a migration, then apply the change so caches refresh more quickly. After the update stabilizes, you can raise TTLs again to reduce query load. If you are mid-change, the best option is to wait for caches to expire.
What does SERVFAIL or a timeout mean?
SERVFAIL or timeouts usually indicate a resolver problem, an unreachable authoritative server, or DNSSEC validation issues at that resolver. It does not always mean the domain is misconfigured. Try again, check a different resolver, and verify the authoritative nameservers are responding. If failures persist across multiple resolvers, review your zone configuration or contact your DNS provider. Comparing with a direct DNS lookup can help narrow the cause.
Which record types can I check here?
This checker supports common record types such as A, AAAA, MX, NS, TXT, and CNAME. These cover most website, email, and verification use cases. If you need other types like SOA or CAA, use the DNS Lookup tool for a direct query. The propagation view focuses on the record types most often updated during migrations and troubleshooting. This keeps results consistent across the selected resolvers.
Sources & references
- RFC 1034: Domain names - concepts and facilities - DNS architecture and terminology.
- RFC 1035: Domain names - implementation and specification - DNS record handling and response format.
- RFC 2308: Negative caching of DNS queries - Explains NXDOMAIN and caching behavior.
- RFC 8484: DNS over HTTPS (DoH) - Defines DNS queries over HTTPS.