IPv4 Subnet Calculator

Enter an IPv4 address and choose a CIDR prefix to calculate the subnet mask, netmask, wildcard mask, network range, usable hosts and shareable subnet link.

Clear

How to calculate IPv4 subnets manually

  1. Convert the IPv4 address and mask to binary (4× octets).
  2. Apply the mask (bitwise AND) to get the network address.
  3. Invert the mask to get the wildcard; OR with network to get broadcast.
  4. First usable = network + 1 (unless /31 or /32). Last usable = broadcast − 1.
  5. Usable hosts = 2^(32−CIDR) − 2 (except /31 = 2, /32 = 1 address).

FAQ

Are subnet calculations stored?

No. Calculations are performed for the result shown and are not stored in a database.

Does the calculator support IPv6?

Yes. The calculator supports both IPv4 and IPv6 subnet calculations.

Can I share a calculation?

Yes. You can copy a shareable link that includes the selected address and prefix in the URL.

Is the calculator free to use?

Yes. The calculator is free to use.