IP Calculator

Calculate network, broadcast address, subnet mask and host range from an IP/CIDR.

IP address / prefix (CIDR)
Network address
192.168.1.0
Broadcast address
192.168.1.255
Subnet mask
255.255.255.0
Wildcard mask
0.0.0.255
First host
192.168.1.1
Last host
192.168.1.254
Total addresses
256
Usable hosts
254
IP class
C
Address type
Private

The IP calculator computes subnet details from an address and CIDR prefix, e.g. "192.168.1.10/24". Enter the address and the tool shows the network address, broadcast address, subnet mask and its wildcard form, the first and last usable host, plus the total and usable address counts.

Useful when configuring network equipment, planning addressing for an office or data center, setting up firewall rules, or just quickly figuring out which subnet an IP belongs to and how many hosts it can hold.

The calculator also identifies the address class (A/B/C/D/E) and whether the address is private (10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16) or public. Everything is computed right in your browser.

Frequently asked questions

A notation of the form IP/N, where N is the number of bits in the subnet mask (0 to 32). For example, /24 means a 255.255.255.0 mask — 256 addresses, 254 of them usable by hosts.
The first address in a subnet is the network address, and the last is the broadcast address. Both are reserved and not assignable to hosts, so usable hosts is 2 fewer than the total (except for /31 and /32).
/32 is a single specific host (0 assignable addresses besides itself). /31 is a special case for point-to-point links (RFC 3021): both addresses in the subnet are used as hosts, so the count of "regular" usable hosts is formally 0.

You may also need

MD5/SHA hashesJWT decoderRegex testerText diffCron to text