Free PTR Record (Reverse DNS) Checker
Look up the hostname an IP address reverse-resolves to.
Need to monitor this across every client domain you manage? ActiScan does bulk scanning, scoring, and white-labeled reporting for MSPs.
What Is a PTR Record?
A PTR (Pointer) record maps an IP address back to a hostname – the opposite direction of an A record. It's set by whoever controls the IP block (usually a hosting provider or ISP), not by whoever owns the domain the hostname belongs to, which is why you often can't add one yourself without going through your host.
- •Reverse-resolving a mail-sending IP to a hostname, as part of email deliverability checks
- •Confirming a server's hostname matches what its hosting provider set
- •Basic network diagnostics – identifying what a given IP is
Example
8.8.8.8 → dns.google.
A reverse lookup resolving Google's public DNS IP back to its hostname.
Things to Know
You usually can't set this yourself
PTR records live in a reverse zone controlled by whoever owns the IP block – typically your hosting provider or ISP. If you run a mail server, you'll usually need to ask them to set it, not your own DNS host.
Missing PTR is a spam signal for mail
Some receiving mail servers treat a mail-sending IP with no PTR record – or one that doesn't match the sending hostname – as suspicious. This matters specifically for outbound mail servers, not general web hosting.
Next Steps
Blacklist Checker
Check whether a sending IP is listed on any major email blacklist.
Blacklist Checker →Frequently Asked Questions
Is this PTR record checker free?
Yes – reverse-lookup any IPv4 address, for free, no signup required.
Why do I enter an IP address instead of a domain?
PTR is a reverse lookup by design – you're asking 'what hostname is this IP,' not 'what IP is this hostname.' Use the A record checker for the forward direction.
My IP has no PTR record at all
That's common for many IPs, especially residential or non-mail-sending ones. It only becomes a real issue if that IP is sending outbound email.
What resolver does this use?
Cloudflare's public DNS-over-HTTPS resolver. Every lookup is live, not a cached snapshot.