schedule

Reset Schedule: 00:00 & 12:00 (GMT+7) Daily

swap_horiz

Reverse DNS Lookup

Find domain names associated with an IP address

swap_horiz Reverse DNS Lookup

Enter IPv4 or IPv6 address for reverse lookup

lightbulb

About Reverse DNS:

Reverse DNS maps IP addresses back to domain names using PTR records. Not all IP addresses have reverse DNS records configured.

help_outline Understanding Reverse DNS

What is Reverse DNS?

Reverse DNS (rDNS) is the process of resolving an IP address to a domain name, which is the opposite of the standard forward DNS lookup that resolves domain names to IP addresses.

How it Works

  • looks_one IP address is reversed (e.g., 8.8.8.8 → 8.8.8.8.in-addr.arpa)
  • looks_two PTR (Pointer) record is queried in DNS
  • looks_3 Domain name is returned if PTR record exists

Common Uses

  • security Email server verification (anti-spam)
  • verified_user Network troubleshooting and diagnostics
  • analytics Log analysis and visitor identification
  • admin_panel_settings System administration and monitoring
warning

Important Note:

Not all IP addresses have reverse DNS records. Many residential and mobile IP addresses may not have PTR records configured.

compare_arrows IPv4 vs IPv6 Reverse DNS

IPv4 Format:

8.8.8.8 → 8.8.8.8.in-addr.arpa

IP is reversed and .in-addr.arpa is appended

IPv6 Format:

2001:db8::1 → 1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa

Hex digits are reversed in nibble format