Reverse DNS Lookup
Look up the hostname or PTR record associated with an IP address. Reverse DNS is important for email deliverability and server identification.
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Results are generated on demand so you can verify the current public configuration.
What is Reverse DNS?
Reverse DNS (rDNS) maps an IP address back to a hostname. While regular DNS translates
domain names to IP addresses, reverse DNS does the opposite using PTR records.
Why is it Important?
Many email servers check reverse DNS before accepting email. If your sending server's IP
doesn't have proper PTR records, your emails may be rejected or marked as spam.
Forward-Confirmed rDNS (FCrDNS):
For maximum deliverability, the PTR record's hostname should resolve back to the original IP
address. This "forward-confirmed" setup is trusted by spam filters.
What does reverse DNS lookup check? +
It checks the PTR record for an IP address to see which hostname the IP resolves back to.
Why is reverse DNS important for email? +
Many receiving mail servers use PTR records as a trust signal. Missing or mismatched reverse DNS can cause rejection or spam placement.
Who controls PTR records? +
PTR records are usually controlled by the IP address owner, such as your hosting provider, cloud provider, or ISP.