IP Subnet Calculator
Calculate subnet mask, broadcast address, host range, and more from CIDR notation.
/24 — Class C
Network address192.168.1.0
Subnet mask255.255.255.0
Broadcast address192.168.1.255
First usable host192.168.1.1
Last usable host192.168.1.254
Usable hosts254
Total addresses256
Wildcard mask0.0.0.255
Network: 11000000.10101000.00000001.00000000
Mask: 11111111.11111111.11111111.00000000
How subnet calculation works
CIDR (Classless Inter-Domain Routing) notation expresses an IP range as an IP address plus a prefix length — e.g. 192.168.1.0/24. The prefix (/24) is the subnet mask in bits: /24 = 255.255.255.0. The calculator derives the network address (IP & mask), broadcast (network | ~mask), first/last usable hosts, and the total number of hosts (2^(32−prefix) − 2). For networking tools, also try Random IP Generator or Common Ports Reference.
Private & free — this tool runs entirely in your browser.
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