Enter a domain and this resolves its DNS records live, straight from this server — no third-party lookup service in the middle.
Reading the results
- A and AAAA are the IPv4 and IPv6 addresses a name points to. Seeing one but not the other is normal; seeing neither is not.
- CNAME is an alias. A name may have a CNAME or an A record, never both — that combination is invalid and is a common cause of a zone that half-works.
- MX records carry a priority. Lower number wins. If mail is landing in the wrong place, the priority is usually why.
- TXT holds SPF, DKIM, DMARC and various verification strings. If mail is going to spam, this is the first place to look.
- NS shows who is authoritative for the zone. If these are not who you think, your DNS change was made in the wrong place.
- SOA contains the serial number, which only moves when a zone is actually published.
- CAA restricts which certificate authorities may issue certificates for the name.
When a record will not resolve
If a record you have just created is not showing, check the recorded TTL before you assume the change failed. A record with a 3600 second TTL can legitimately take an hour to appear everywhere, and the value you are seeing may be a cached copy from before your edit.
The other common cause is a missing trailing dot. In a zone file, mail.example.com is treated as relative and becomes mail.example.com.example.com, while mail.example.com. with the dot is absolute. If you see a doubled domain in the results, that is almost always what happened.
A note on privacy
The lookup runs from this server’s resolver, not from your browser to a public resolver, so the query is not shared with a third party alongside your IP address. I keep a short-lived count of lookups per connection purely to stop the endpoint being abused — nothing is logged against the domain you searched.