Reverse DNS Lookup
Build the expected PTR name for an IPv4 address and check a pasted PTR record against it.
Runs in your browser. Nothing is uploaded — your input is processed on this device and discarded when you close the tab.
Reverse DNS Lookup
How to use this tool
- Enter your values in the fields above.
- Press Generate to see the result.
- Use Load sample to try the worked example, Copy result to copy it, or Clear to start again.
Worked example
Address 1.2.3.4 gives the expected PTR name 4.3.2.1.in-addr.arpa, which matches the pasted record.
What this tool does not do / Limits
This builds and validates the expected PTR name from the address you enter. It does not perform a live DNS lookup or prove what a DNS server returns.
Frequently asked questions
Does it look up the address live?
No. It builds the expected PTR name from the address itself.
What is a PTR name?
The reversed address plus the reverse-DNS suffix, used to map an address back to a name.
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