Time To Live — how many seconds a resolver may cache this record before asking the authoritative server again.

Why do MX records have priority numbers?

Lower numbers are tried first. It lets domains declare a primary mail server and fallbacks in one record set.

What does NXDOMAIN mean?

The DNS server answered authoritatively that the name does not exist. It is different from an empty result, which means the name exists but has no records of the requested type.

DNS Lookup

Query DNS records for any hostname. Select a record type and see the results from the server's perspective.

A — IPv4 address the hostname points to.

DNS translates a hostname into the data network software needs to route email, resolve addresses, and verify ownership. Pick an example to see what the public DNS returns.

Try an example

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