IP Subnet Calculator

Calculate IPv4 subnets with CIDR notation

Enter Network Information

Provide an IP address and CIDR notation to calculate subnet details

Example: 192.168.1.0, 10.0.0.0, 172.16.0.0

Subnet mask bits (0-32)

About Subnet Calculation

CIDR (Classless Inter-Domain Routing) notation is a compact method for specifying IP addresses and their routing prefix. The number after the slash (/) represents the number of bits in the network portion of the address.

  • /24 = 255.255.255.0 (254 usable hosts)
  • /16 = 255.255.0.0 (65,534 usable hosts)
  • /8 = 255.0.0.0 (16,777,214 usable hosts)
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