IP network calculator

Inspect an IPv4 or IPv6 CIDR network without listing its hosts.

Text Stateless

Maximum input length per field: 49 Unicode code points. See the operation limits in the instructions.

Quick guide

Try it with your own data when you’re ready.

Try an example

You enter

Address and prefix, such as 192.0.2.129/24
192.0.2.129/24

You get

Normalized network
192.0.2.0/24
IP version
4
Prefix length
24
Network mask
255.255.255.0
First address (inclusive)
192.0.2.0
Last address (inclusive)
192.0.2.255
Total addresses (including endpoints)
256
How it works & limits

Use a numeric CIDR prefix. Host bits are normalized to the network address.

Results show the full address range and total count, not the number of usable hosts; no addresses are enumerated. IPv6 has no broadcast semantics here: the last-address field is simply the end of the range.