IPv4 CIDR Calculator

Enter an IPv4 address and subnet mask in CIDR notation (e.g., 192.168.1.0/24) to calculate network details.

This tool calculates:

  • Network Address
  • Broadcast Address
  • Netmask
  • First Usable Host IP
  • Last Usable Host IP
  • Total Number of Hosts
  • Number of Usable Hosts
Note: Handles /31 (RFC 3021) and /32 correctly. IPv6 is not currently supported.