---
title: "PTR record"
description: "A PTR record performs reverse DNS: it maps an IP address to a domain name. Learn its role in email deliverability and who can set it."
url: "https://nodea.io/en/glossary/ptr-record"
lang: "en"
updated: "2026-07-13"
---

# PTR record

> A PTR (pointer) record is a reverse-DNS entry that maps an IP address to a domain name — the inverse of an A record and key to mail server reputation.

A **PTR record** (*pointer record*) is a [reverse-DNS](https://nodea.io/en/glossary/rdns-reverse-dns) entry that maps an IP address back to a domain name. It is the inverse of an [A record](https://nodea.io/en/glossary/a-record): where an A record answers "which IP does this name have," a PTR record answers "which name is behind this IP."

## What a PTR record involves

Reverse DNS lookups happen in a special *in-addr.arpa* zone (for IPv4) or *ip6.arpa* (for IPv6), where the IP address is written in reversed order. The key difference from other records: a PTR is published in a zone belonging to the **owner of the IP address pool**, not the domain owner. In practice this means:

- the PTR record is set by the hosting, VPS or network provider,
- you cannot change it in your own domain's ordinary DNS panel,
- good practice is for the PTR and the [A record](https://nodea.io/en/glossary/a-record) to point at each other consistently (forward-confirmed rDNS).

## The PTR record in practice

The PTR record's most important role is mail server reputation. Receiving [SMTP](https://nodea.io/en/glossary/smtp) systems check whether the sender's IP has a valid, matching PTR record — its absence or a default "generic" provider name often means the message is rejected outright or flagged as spam. That is why, when running your own mail server on a [VPS](https://nodea.io/en/glossary/vps), configuring the PTR record — alongside SPF, DKIM and DMARC — is one of the first steps. Beyond email, rDNS is also used in logs and diagnostic tools.

### Who sets a PTR record — the domain owner or the IP provider?

A PTR record is set by the owner of the IP address, usually the hosting, VPS or network provider — you cannot add it in an ordinary domain DNS panel. The change happens in the reverse zone tied to the IP address pool, so rDNS is typically configured through the server provider's panel or a support request.

## Related

- [rDNS](https://nodea.io/en/glossary/rdns-reverse-dns)
- [A record](https://nodea.io/en/glossary/a-record)
- [DNS](https://nodea.io/en/glossary/dns)
- [SMTP](https://nodea.io/en/glossary/smtp)
- [IP Address](https://nodea.io/en/glossary/ip-address)

---

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