Reverse DNS Lookup
Find the hostname (PTR record) associated with an IP address
DNS Resolution Result
PTR Record Details
IP Information
Geographic Location
Map will appear after lookup
No location data yet
Location is approximate
About Reverse DNS
Learn more & FAQ
What is a reverse DNS lookup?
A forward DNS lookup turns a hostname into an IP address. Reverse DNS does the opposite: given an IP address, it finds the PTR record stored in the special reverse zone (in-addr.arpa for IPv4, ip6.arpa for IPv6) and returns the hostname attached to it. It's one of the quickest ways to identify what a server actually is from nothing but its IP.
How to read your results
The DNS Resolution Result card shows the hostname the IP resolved to, alongside response time and which DNS server answered. PTR Record Details gives you the raw record itself. The IP Information and Geographic Location cards add context (ISP, ASN, approximate location) so you can sanity-check whether the hostname matches what you'd expect for that network - handy when you're tracing a suspicious log entry or verifying a mail server's setup.
Frequently asked questions
What is a reverse DNS (PTR) lookup?
A reverse DNS lookup takes an IP address and finds the hostname it resolves back to, using a PTR record stored in the reverse DNS zone. It's the mirror image of a normal lookup, which turns a hostname into an IP address.
Why would I need to look up the hostname for an IP?
It's commonly used to identify what a server is (hosting provider, mail server, CDN node) from logs or connection records, and to troubleshoot email deliverability - many mail servers reject or flag messages from IPs with no matching PTR record.
Why does my IP have no PTR record?
Not every IP has one set up. Residential and many cloud IPs ship with a generic or missing PTR record by default; setting a custom one usually requires asking your hosting provider or ISP, since PTR records live in a reverse zone they control.
Does a PTR record have to match the forward (A) record?
Not strictly, but for mail servers it should - this is called forward-confirmed reverse DNS (FCrDNS), and a mismatch is one of the most common reasons receiving mail servers mark outgoing email as spam.
Does this tool work for both IPv4 and IPv6?
Yes - enter either an IPv4 address (e.g. 8.8.8.8) or an IPv6 address and the tool resolves the matching PTR record for either.