What this does
Your browser sends the query to public resolvers using DNS over HTTPS, so the answers are what those resolvers see right now. Comparing two resolvers is a quick way to check whether a recent DNS change has reached caches.
Reading the result
- NOERROR with records: the name resolved.
- NOERROR without records: the name exists but has no record of that type.
- NXDOMAIN: the name does not exist.
- SERVFAIL: the resolver could not get an answer, often a configuration or DNSSEC problem.
- TTL is the seconds this resolver will still keep the answer. It counts down between queries.
If the two resolvers disagree
One of them still holds an old cached answer. Wait for the TTL to expire. See how this works in our DNS lesson on caching and propagation.
Queries go from your browser to Cloudflare and Google, so those services see the domain you look up and your IP address.