CIDR / subnet

Enter an address with a prefix like 192.168.1.0/24 and instantly get the network and broadcast addresses, mask, wildcard, host range and counts.

Enter an address with a prefix like 192.168.1.0/24 and instantly get the network and broadcast addresses, mask, wildcard, host range and counts.

How to use

  1. Type an IPv4 CIDR such as 10.0.0.0/8 or a bare IP (treated as /32)
  2. Read off network, broadcast, netmask and wildcard
  3. Check the usable host range and total addresses
  4. Click any value to copy it

Frequently asked questions

What do /31 and /32 mean here?

/32 is a single host; /31 is a two-host point-to-point link (RFC 3021). Both are handled explicitly.

How is «usable hosts» computed?

Total addresses minus network and broadcast for /30 and larger; /31 gives 2 and /32 gives 1.

Is a private range detected?

Yes — 10/8, 172.16/12 and 192.168/16 are marked private, everything else public.