DNS
What is PTR Record (Pointer Record)?
A reverse-DNS record that maps a sending IP address back to a hostname.
A PTR record lives in the reverse DNS zone (in-addr.arpa for IPv4) and resolves an IP address to a domain name, the inverse of an A record. For mail, receiving servers look up the sending IP's PTR to confirm it has a valid hostname, ideally one that matches the forward A record, a check known as forward-confirmed reverse DNS (FCrDNS). PTR records are set by whoever controls the IP block, typically the host or ESP, not the sending-domain owner.
Why it matters for cold email
Many mailbox providers reject or spam-folder mail from IPs that lack a valid, matching PTR record. For cold email on a dedicated IP, a missing or generic PTR is an immediate trust penalty, so confirming proper reverse DNS is a baseline deliverability check before any campaign.
Related terms
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