PTR Record Explained (Reverse DNS in Plain English)

A PTR record is the DNS record used for reverse lookups - mapping an IP address back to a hostname.

PTR records in one sentence

PTR (Pointer) records live under in-addr.arpa (IPv4) or ip6.arpa (IPv6) and return a hostname for an IP.

Where PTR records live (DNS zones)

A PTR record is stored in a reverse DNS zone. For IPv4 it'sin-addr.arpa (octets reversed). For IPv6 it'sip6.arpa (nibbles reversed). These zones are usually delegated to the ISP or hosting provider that owns the IP block.

Forward-confirmed reverse DNS (FCrDNS)

Many systems check that a PTR hostname resolves back to the same IP. This forward-and-reverse match is called FCrDNS and is often required for email servers.

Where PTR records are used

• Email servers: PTR presence and consistency is a common spam signal
• Logs: converting IPs to names can improve readability
• Diagnostics: seeing a network's naming conventions can be useful

Can I edit my PTR record?

Usually only the IP owner (ISP or hosting provider) can set PTR records for that range. If you need a custom PTR, you must request it from your provider.

Try a live lookup with our Reverse DNS (PTR) tool.

Glossary: PTR and Reverse DNS.