Free Reverse IP Lookup
Map an IP address back to its hostname using the PTR record. Works for both IPv4 and IPv6.
How it works
Paste an IP
IPv4 (8.8.8.8) or IPv6 (2606:4700::1111). Both supported.
We query the PTR zone
in-addr.arpa for IPv4, ip6.arpa for IPv6 — the standard reverse-DNS path.
Get the hostname
Returned as a list — most IPs have one PTR, but technically more than one is allowed.
Frequently asked questions
Why is there no PTR for my IP?+
PTR records are set by the IP owner (your hosting provider or ISP). Not all IPs have one — especially residential and budget VPS ranges.
Why does the hostname not resolve back to the IP?+
PTR and A records are completely independent. Many providers set a default PTR (like ec2-1-2-3-4.compute-1.amazonaws.com) that doesn't roundtrip to the original IP if you re-resolve it.
Does this work for private IPs?+
No. We block private and reserved ranges for security reasons. Reverse lookups for those use your local resolver anyway.
Is PTR useful for anything besides debugging?+
Yes — mail server reputation. Many SMTP servers reject mail from IPs that don't have a matching forward-confirmed reverse DNS (FCrDNS) record.
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