Does this IP’s reverse DNS check out?
Checks an IP’s reverse DNS and confirms it resolves back — enter the IP your mail server sends from.
Example result
1 name
PTR record
8.8.8.8 has a reverse DNS name: dns.google. That is the name a receiving mail server sees when this address connects. Whether it stands up to the check they actually run is the next row.
8.8.8.8 → dns.googleForward-confirmed
Forward confirmation
dns.google was resolved forward and it points back at 8.8.8.8. That round trip is the check receiving mail servers actually perform — the forward lookup was really made here, not assumed from the PTR — and this address passes it. This is the state a sending IP wants to be in.
dns.google → 8.8.8.8 ✓Example result · public DNS lookups only, in both directions · nothing stored · no account