What it reads
For each mail server address: the reverse record, and whether that name resolves back to the same address.
Check 13 of 54 · Email authentication
Reverse DNS, explained.
Whether your mail servers have the reverse DNS receivers expect. Without it, mail gets marked down.
Engine 1.57.0, read 25 October 2026
Free checkScoredReliability: High
Can someone send email as you?
What the check does, and where it stops.
Why it matters
Many receivers mark down or refuse mail from a server whose name and address do not match in both directions.
What a failure looks like
A failure is a finding in your result. The check is scored, so it can lower your score, and the Full Report gives every finding its severity and a fix. If the check cannot finish, it is recorded as unknown: it carries no penalty, and it is never a pass.
Where its limits are
Reads your inbound mail servers. A provider that sends from a separate pool is a small blind spot.
ReliabilityHigh: narrow, known blind spots
Check 13 is one of 16 in Email authentication. See it in its row on the scanner page, beside the rest of Email authentication.
See how your domain does.
The free check includes this one and takes about 30 seconds. No account. Nothing to install.