Reverse DNS
Generate PTR record names and reverse zone files from IPv4/IPv6 addresses, or perform live reverse lookups.
Try Reverse DNS →What It Does
The Reverse DNS tool has two modes: PTR Generator converts an IP address into its reverse DNS name (in-addr.arpa for IPv4, ip6.arpa for IPv6) and generates the DNS zone entry. Live Reverse Lookup queries public DNS to find the hostname associated with an IP address.How to Use It
- Navigate to DNS Tools → Reverse DNS from the top menu.
- Choose a mode: PTR Generator (offline, instant) or Live Reverse Lookup (queries DNS).
- Enter an IPv4 or IPv6 address.
- Click Generate or Lookup.
- View the PTR name, reverse zone, and DNS entry (generator) or the resolved hostname (lookup).
- Use Copy All or Download .txt to export.
IPv4 vs IPv6 Reverse DNS
- IPv4: Octets are reversed and appended to
in-addr.arpa. Example:192.168.1.1becomes1.1.168.192.in-addr.arpa. - IPv6: Each hex nibble is reversed and dot-separated, appended to
ip6.arpa. Example:2001:4860:4860::8888expands and reverses to a long.ip6.arpaname.
Use Cases
- Email server setup: Mail servers need matching PTR records for deliverability.
- Incident response: Identify the hostname behind a suspicious IP address.
- DNS delegation: Generate correct zone names when delegating reverse DNS zones.
- Network documentation: Export PTR entries for DNS zone files.