CIDR / Subnet Calculator

Calculate IPv4 and IPv6 subnets — network, broadcast, host range, mask, and usable host count from a CIDR.

CIDR or IP address

Accepts IPv4 (192.168.1.0/24) and IPv6 (2001:db8::/32). Bare addresses are treated as /32 or /128.

CIDR192.168.1.0/24

Network192.168.1.0

Broadcast192.168.1.255

First host192.168.1.1

Last host192.168.1.254

Subnet mask255.255.255.0

Wildcard mask0.0.0.255

Mask (binary)11111111.11111111.11111111.00000000

Total addresses256

Usable hosts254

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