IP Subnet Toolkit

Subnet and Range Calculation Tools

This tool allows you to specify an IP and a subnet scope in various formats including V4 and V6, and will then calculate the CIDR, Network, Broadcast, Netmask and the range. This is especially useful for sub 256 blocks where knowing the Network and Broadcast addresses is important. Enter one of the following:

  • an IPv4 address in CIDR notation (e.g.
  • an IPv4 Address in NETMASK notation (e.g.
  • an IPv4 Address as a range (e.g.
  • an Ipv6 Address in CIDR notation (.e.g. 2001:0db8:85a3::8a2e:0370:7334/64)
  • an Ipv6 Address as a range (e.g. 2001:0db8:85a3::8a2e:0370:7334-2001:0db8:85a3::8a2e:0370:733f)


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