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IP Lookup Tools Reverse DNS (PTR) Lookup

Reverse DNS (PTR) lookup and forward confirmation

See an IP address's reverse DNS (PTR) name and whether that name resolves back to the same IP address (forward-confirmed reverse DNS, FCrDNS). It is the check Google and other receivers run on mail-sending servers.

If you enter a domain name, its A record is resolved and the first public IP address is looked up.

What is checked?

  • The PTR record: the IP address's reverse DNS name (under in-addr.arpa and ip6.arpa)
  • Forward confirmation: the PTR name is resolved again with A or AAAA and checked for the same IP address
  • In the same card: ASN, IP block, registration (RIR) data and a hint whether the name suggests a static or dynamic address

How do I read the result?

  • If there is no PTR record, reverse DNS has not been set for this IP address. The owner of the IP block (the hosting or internet service provider) adds it; it cannot be added in your domain's DNS panel.
  • If forward confirmation says "No", the PTR name resolves to another address or not at all; fix it on the mail-sending server.
  • Websites do not need a PTR record; servers that send email do.

Frequently asked questions

Where can I add a PTR record?

From the organization that assigned the IP address to you: your hosting provider on shared hosting, or the provider's panel or support team on a VPS or server. A PTR record cannot be added in a domain's DNS panel.

Why does forward confirmation matter?

Receiving servers take the sending IP address's PTR name and check that the name resolves back to the same IP address. Google's sender requirements ask for this from all senders.