Free Reverse DNS Tool
Free reverse DNS lookup tool — find PTR records for any domain's IP addresses. Verify server hostnames and check email deliverability configuration.
What Is Reverse DNS?
Reverse DNS (rDNS) uses PTR records to map IP addresses to hostnames — the opposite of a standard A record lookup. For IPv4, reverse lookups query the in-addr.arpa zone.
Properly configured reverse DNS is critical for email deliverability. Most spam filters check that the sending server's IP has a valid PTR record matching the server's hostname.
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