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IP Addressing

Subnet Calculator

Enter an IP with its prefix and instantly get the network, mask, wildcard, host range, broadcast, class and type.

Accepts IP/CIDR, IP mask or just IP.

255.255.255.192 64 addresses

Subdivide into subnets (VLSM)

Hosts each subnet needs, within 192.168.10.0/26.

redzilla.cl — subnet
$ calc 192.168.10.0/26

Network192.168.10.0
Mask255.255.255.192 (/26)
Wildcard0.0.0.63
Range192.168.10.1  192.168.10.62
Broadcast192.168.10.63
Hosts62 usable (64 total)
ClassC
TypePrivate (RFC 1918)
$ 
Network 192.168.10.0
Mask 255.255.255.192
First host 192.168.10.1
Last host 192.168.10.62
Broadcast 192.168.10.63

Binary representation

network bits host bits

Runs locally in your browser · no sign-up · nothing leaves your browser.

How it works

The calculator takes an IPv4 address and a prefix (for example 192.168.1.0/26) and breaks the subnet down: dotted-decimal mask, wildcard, network address, usable host range, broadcast, historical class and network type (private, public or special).

It performs the same operation a router does: it ANDs the mask with the address to get the network, inverts the mask for the wildcard, and uses the host bits to count addresses: 2^(32−prefix) in total, minus network and broadcast for usable hosts (with the /31 and /32 exceptions).

Example: how many devices fit in 192.168.1.0/26?

  1. A /26 prefix leaves 32 − 26 = 6 bits for hosts.
  2. 2^6 = 64 total addresses in the block (.0 through .63).
  3. Subtract network (.0) and broadcast (.63): 62 usable hosts, .1 through .62.

Frequently asked questions

How many hosts does a /24, /26 or /30 have?
A /24 has 254 usable hosts, a /26 has 62 and a /30 has 2. The general formula is 2 to the power of (32 minus the prefix), minus 2 (network and broadcast addresses). The /31 (point-to-point links, RFC 3021) and /32 (single host) cases skip the subtraction.
What is the difference between mask and wildcard?
They are the same information written backwards: the mask sets ones on the network part (255.255.255.192) while the wildcard sets ones on the host part (0.0.0.63). Devices use the mask on interfaces; Cisco ACLs and OSPF use the wildcard.
Why can I not use the first and last address of the subnet?
The first identifies the whole network and the last is the segment broadcast: sending there reaches every device in the subnet. By convention neither is assigned to a host, except on /31 and /32.
Does the calculator work offline?
Yes. Everything runs in your browser: no IP address is ever sent to a server, so you can use it with internal network data without exposing it.
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Disclaimer We take great care to keep every tool accurate and review it thoroughly; even so, we can't guarantee it is free of errors or take responsibility for how the results are used. We recommend double-checking anything critical.
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