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DNS & Network Tool

Reverse DNS Lookup

Enter an IPv4 or IPv6 address to find its reverse DNS hostname and PTR record. Quickly check whether an IP address resolves back to a domain or server hostname.

PTR Lookup
IPv4 & IPv6
Forward Check
Fast Results
Reverse DNS Flow
DNS Ready
Reverse DNS lookup network illustration Diagram showing an IP address resolving through DNS to a hostname. IP ADDRESS 8.8.8.8 DNS PTR RECORD dns.google REVERSE LOOKUP IP → Hostname
PTR Reverse Record
IPv4 Supported
IPv6 Supported

Check an IP Address

Enter an IPv4 or IPv6 address below to discover its reverse DNS hostname and PTR record.

Reverse DNS Lookup IP address to hostname lookup
DNS Ready
IPv4 OR IPv6
Enter an IP address, not a domain name. Reverse DNS converts an IP address into its associated hostname.
Try an example
Querying reverse DNS... Checking the PTR record for this IP address.
PTR Record Found
Reverse DNS Hostname
dns.google
IP Address
—
IP Version
—
Forward Confirmation
—
Lookup Time
—
Hostname Forward DNS Addresses

What Is Reverse DNS Lookup?

Reverse DNS lookup is the process of finding the hostname associated with an IP address. Instead of starting with a domain name and looking for its IP address, reverse DNS starts with the IP and searches for a PTR record.

PTR stands for Pointer Record. It is a DNS record used to map an IPv4 or IPv6 address back to a hostname.

Forward DNS vs Reverse DNS

A normal forward DNS lookup typically converts a hostname such as example.com into an IP address. Reverse DNS performs the opposite operation by checking whether an IP address has a hostname assigned through a PTR record.

What is Forward Confirmation?

After a PTR hostname is discovered, this tool also checks the hostname's forward DNS records. If the original IP appears in those records, the reverse and forward DNS information is considered confirmed.

reverse-dns-check
$ reverse-dns 8.8.8.8

Querying PTR record...
IP: 8.8.8.8
Type: IPv4
PTR: dns.google
Forward check: confirmed

✓ Reverse DNS lookup completed.

Why Use Our Reverse DNS Lookup?

Quickly inspect PTR records and IP-to-hostname relationships without using command-line tools.

Fast PTR Lookup

Enter an IP address and receive its reverse DNS hostname without manually running DNS commands.

IPv4 & IPv6

The lookup accepts both standard IPv4 addresses and modern IPv6 addresses.

Forward Verification

The discovered hostname can be resolved forward to check whether it points back to the original IP address.

Browser Friendly

Results are displayed in a simple interface without requiring terminal commands or additional software.

When Is Reverse DNS Useful?

PTR lookups are commonly used by administrators, email professionals, developers and security teams.

Email Servers

Reverse DNS is commonly checked when reviewing mail server configuration and email deliverability settings.

Server Administration

Identify hostnames assigned to servers, VPS addresses and other network infrastructure.

Security Investigation

Add hostname context when examining IP addresses found in logs, alerts and network activity.

Development

Developers can quickly inspect reverse DNS behavior while testing networking and infrastructure configurations.

Cloud Infrastructure

Check whether public cloud and hosted IP addresses have recognizable PTR hostnames.

Troubleshooting

Reverse DNS information can help diagnose hostname, DNS and server identity issues.

How to Use Reverse DNS Lookup

Find an IP address's PTR hostname in three simple steps.

1

Enter an IP Address

Paste or type the IPv4 or IPv6 address that you want to investigate.

2

Run the Lookup

Click Lookup DNS. The server requests the reverse DNS hostname for the IP address.

3

Review the PTR Result

View the hostname, IP version, lookup time and forward DNS confirmation information.

Reverse DNS Lookup FAQs

Common questions about PTR records, IP addresses and reverse DNS.

A reverse DNS lookup checks an IP address to find the hostname assigned to it through a PTR record.
A PTR, or Pointer, record is a DNS record that maps an IP address back to a hostname. It is essentially the reverse of a standard DNS address lookup.
Not every IP address has a PTR record. The organization controlling the IP address must configure reverse DNS for a hostname to be returned.
Yes. IPv6 supports reverse DNS using PTR records in the special ip6.arpa DNS namespace. This tool accepts both IPv4 and IPv6 addresses.
No. A normal DNS lookup commonly starts with a hostname and returns an IP address. Reverse DNS starts with an IP address and attempts to return a hostname.
Mail systems often inspect reverse DNS as one signal when evaluating the identity and configuration of a sending mail server. A properly configured PTR record can therefore be an important part of mail server setup.
Forward-confirmed reverse DNS means an IP resolves to a hostname through reverse DNS, and that hostname resolves forward to the original IP address.
Yes. The Reverse DNS Lookup can be used online without creating an account or installing command-line software.