IPv4 & IPv6 Subnet Calculator
Enter an IP address and prefix length (or netmask) to compute network details. Tabs let you switch between IPv4 and IPv6.
2) Results (IPv4)
Address
CIDR
Netmask
Wildcard mask
Network
Broadcast
First host
Last host
Usable hosts
Class
Scope
Binary
Hex
Reverse DNS
2) Results (IPv6)
Address (compressed)
Address (full)
CIDR
Prefix length
Netmask (128-bit)
Network
First address
Last address
Total addresses
Type / Scope
Reverse DNS
February 19, 2026