Query the same record across Google, Cloudflare, AdGuard and Quad9 at once, and see instantly whether the answer is consistent or still catching up. Free, no signup.
Pick one record type, then check it across every resolver at once. Data comes over DNS-over-HTTPS from public resolvers.
Check DNS propagation.
Enter a domain above to query it across every resolver at once.
The propagation command queries the record across every resolver and tells you if it is consistent, with a --json mode for scripting.
# check A record propagation across resolvers
python cli.py propagationgithub.com--typeA# full structured JSON (per-resolver values, consistent flag)
python cli.py propagationgithub.com--typeA--json
THE BIG DIFFERENCE
Check propagation from inside your AI
This tool speaks the Model Context Protocol (MCP) and ships a REST API. Connect it once, then just ask your assistant whether a domain's DNS change has gone live everywhere.
DNS propagation is the time it takes for a change to a domain's DNS records to be seen everywhere on the internet. When you update an A, MX or any other record, resolvers around the world do not pick it up instantly. Each one keeps serving the record it already cached until that cached copy expires, so for a while some resolvers return the new value while others still return the old one. A DNS propagation checker queries the same record from several independent resolvers at once so you can see exactly where the change has landed.
How to check DNS propagation
Type the domain (for example github.com) into the box above.
Choose the record type you changed, such as A, MX or TXT. A is the default.
Select Check. The tool queries every resolver at the same time.
Read the verdict: consistent means the change has propagated, mismatch means some resolvers are still serving the old record.
Why do resolvers return different answers?
Every resolver caches DNS answers independently. When you ask a resolver for a record, it returns whatever it has cached and only fetches a fresh copy from the authoritative nameservers once that cache expires. Because each resolver cached the record at a different moment, right after a change some will already hold the new value while others still hold the old one. That is not an error, it is DNS caching working as designed, and it is exactly the state this tool surfaces as a mismatch.
How TTL controls propagation speed
The TTL (time to live) on a record tells resolvers how many seconds they may cache it before checking again. A record with a TTL of 3600 can be cached for up to an hour, so a change may take up to an hour to reach a resolver that just refreshed. If you know a change is coming, lower the TTL a day or two beforehand (for example to 300 seconds) so resolvers refresh more often, then the change propagates in minutes instead of hours. After the change has settled, you can raise the TTL again to reduce load.
Which resolvers this tool checks
Google (8.8.8.8): the most widely used public resolver.
Cloudflare (1.1.1.1): a fast, privacy-focused public resolver.
AdGuard: a public resolver with filtering, popular in consumer setups.
Quad9 (9.9.9.9): a security-focused resolver that blocks known malicious domains.
Frequently asked questions
What is a DNS propagation checker?
A DNS propagation checker queries the same DNS record from several independent public resolvers at once and compares their answers. If every resolver returns the same values, the change has propagated. If they disagree, some resolvers are still serving the old cached record. This tool checks Google, Cloudflare, AdGuard and Quad9.
How long does DNS propagation take?
Propagation is governed by the record's TTL. A resolver caches an answer for up to the TTL, so a change can take anywhere from a few seconds to 24 or 48 hours to appear everywhere, depending on the TTL set before the change. Lowering the TTL ahead of a planned change makes propagation faster.
Is the DNS propagation checker free and open source?
Yes. It is completely free and open source under the MIT license, part of WebToolsHub by Konko Maji. It queries public DNS-over-HTTPS resolvers, so there is no signup and no data is stored.
Why do different resolvers show different DNS records?
Each resolver caches records independently and only refreshes them when its cached copy expires after the TTL. Right after a change, some resolvers already have the new record while others still serve the old one from cache, which is exactly what this tool shows as a mismatch.
Can I check DNS propagation inside Claude, ChatGPT or Gemini?
Yes. It ships an MCP server and a REST API, so you can connect it to Claude, ChatGPT, Gemini, Kimi, Cursor and any MCP client, then ask your assistant whether a domain's DNS has propagated across resolvers. See the connection guide.