Subnet / CIDR Calculator
Calculates everything about an IPv4 subnet from CIDR notation: network and broadcast address, usable host range and count, netmask and wildcard mask — plus an IP converter between dotted decimal, integer, hex and binary.
Runs 100% in your browser — nothing you paste leaves your device.
Read the full guide to this tool
Notes
- A /24 has 254 usable hosts: 256 addresses minus the network and broadcast addresses.
- /31 point-to-point links (RFC 3021) use both addresses; a /32 is a single host route.
- Runs 100% in your browser — nothing you paste leaves your device.
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