127.0.0.1 in reverse DNS format:
1.0.0.127.in-addr.arpa
Convert IPv4 and IPv6 addresses into reverse DNS record formats for PTR records in DNS zones.
By using the Reverse DNS generator tool on this page, you can instantly generate PTR records by converting any valid IPv4 or IPv6 address into its corresponding entry required for a reverse DNS PTR record. You simply need to enter the address and press the convert button.
DNS records used for Reverse DNS lookups, known as PTR records are represented in a different format depending on whether they are for IPv4 or IPv6 addresses. They are stored as a special entry in the DNS zone for the .arpa domain. IPv4 addresses are within .in-addr.arpa while IPv6 addresses are under .ip6.arpa.
In order to create a PTR record used for reverse DNS for the corresponding IPv4 A record forward lookup, the IP address will need to be converted in a specific way and placed in the .in-addr.arpa zone.
The following set of rules uses the example IPv4 address: 127.0.0.1
.) - 127.0.0.1 becomes 127, 0, 0, 11, 0, 0, 127.) - 1.0.0.127.in-addr.arpa to the end of the address - 1.0.0.127.in-addr.arpaIn order to create a PTR record used for reverse DNS for the corresponding IPv6 AAAA record forward lookup, the IP address will need to be converted in a specific way and placed in the .ip6.arpa zone.
This address must be generated from the fully expanded IPv6 address to ensure consistency.
The following set of rules uses the example IPv6 address: 2002:7f00:1::
2002:7f00:1:: becomes 2002:7f00:0001:0000:0000:0000:0000:0000:) - 2002:7f00:0001:0000:0000:0000:0000:0000 becomes 20027f0000010000000000000000000000000000000000000000100000f72002.) between each character - 0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.1.0.0.0.0.0.f.7.2.0.0.2.ip6.arpa to the end of the address - 0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.1.0.0.0.0.0.f.7.2.0.0.2.ip6.arpaAny valid IP address can be converted into their corresponding reverse DNS entry, below are a few examples:
| IP Address | Reverse DNS Record | Description |
|---|---|---|
| 127.0.0.1 | 1.0.0.127.in-addr.arpa | IPv4 Reverse DNS record |
| 192.168.1.2 | 2.1.168.192.in-addr.arpa | IPv4 Reverse DNS record |
| 2002:7f00:1:: | 0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.1.0.0.0.0.0.f.7.2.0.0.2.ip6.arpa | Compressed format IPv6 Reverse DNS record |
| 2002:7f00:0001:0000:0000:0000:0000:0000 | 0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.1.0.0.0.0.0.f.7.2.0.0.2.ip6.arpa | Expanded format IPv6 Reverse DNS record |