What is reverse DNS (PTR) and why it matters

Normal DNS translates a name into an IP. Reverse DNS does the opposite: it translates an IP into a name, through a PTR record. It matters most for servers that send email.

Why it matters

Email servers check whether the sender's IP has a PTR that matches the domain name. Without correct reverse DNS, your messages often land in spam or are rejected.

How to check the current PTR

dig -x 203.0.113.10 +short

It should return your server's name (for example mail.example.com).

How to set the PTR for your server

The PTR record is not set in the domain's DNS panel but at the server's network level. On our platform, you send us a request through support with the desired name (for example mail.example.com) and we configure it for your server's IP.

Full match (FCrDNS)

For the best reputation, make sure that:

• the name has an A record to the IP (forward),
• the IP has a PTR to the same name (reverse).

See also SPF, DKIM and DMARC records for maximum email delivery.