How it works
How to use the IP to Hostname (Reverse DNS)
Enter an IP address
Enter an IPv4 or IPv6 address.
Look it up
Press Look up (or Enter). Results arrive in milliseconds over encrypted DNS-over-HTTPS.
Copy the records
Each record has a copy button; the TTL shows how long resolvers cache it.
About the IP to Hostname (Reverse DNS)
Do a reverse DNS (PTR) lookup to find the hostname configured for an IPv4 or IPv6 address — useful for checking mail servers, which should have matching forward and reverse DNS.
Built for developers
Why developers use it
Private by design
Runs 100% in your browser. Nothing you paste is uploaded, logged or stored on a server.
Instant results
Output updates as you type, with precise error locations when something is wrong.
Works offline
Once loaded, the tool keeps working without a connection. Install it as an app if you like.
Free, no sign-up
No accounts, no limits, no watermarks.
FAQ
Frequently asked questions
Where do the DNS answers come from?
From Cloudflare’s public resolver (1.1.1.1) via DNS-over-HTTPS. Results are what the public internet sees — the same answers your browser would get — and are cached by the resolver for the record’s TTL.
Why do my recent DNS changes not show up yet?
Resolvers cache records for their TTL. After changing a record, the old value can be served until the previous TTL expires — typically minutes to a few hours.
Is my data uploaded anywhere?
No. Everything runs locally in your browser — nothing you type, paste or open is sent to a server, logged or stored. The tool keeps working offline once the page has loaded.
Keep going
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