IP Subnet Calculator

Calculate IP subnets, CIDR notation, VLSM, and network ranges for efficient network planning.

Professional Network Planning Tools

Comprehensive calculators for network engineers, system administrators, and IT professionals

Subnet Calculator

IPv4 subnet calculation

CIDR Calculator

Classless routing notation

VLSM Planning

Variable length subnetting

IP Lookup

Network information finder

Basic Subnet Calculator

Enter IP address and subnet mask or CIDR notation

Enter an IP address and subnet mask to calculate network information

VLSM Calculator

Variable Length Subnet Masking - Plan multiple subnets

Enter a base network and subnet requirements to calculate VLSM allocation

IP Address Lookup

Get detailed information about any IP address

Enter an IP address to get network class, type, and binary representation

Binary Calculator

Convert between decimal and binary IP addresses

Enter IP address and subnet mask to see binary representation and network calculations

CIDR Notation Reference

CIDR Subnet Mask Hosts CIDR Subnet Mask Hosts
/8 255.0.0.0 16,777,214 /20 255.255.240.0 4,094
/16 255.255.0.0 65,534 /24 255.255.255.0 254
/18 255.255.192.0 16,382 /28 255.255.255.240 14
/19 255.255.224.0 8,190 /30 255.255.255.252 2

IP Subnet Calculator Features

  • Calculate IPv4 subnets with CIDR notation and subnet masks
  • VLSM (Variable Length Subnet Masking) planning for efficient IP allocation
  • IP address lookup with network class identification and binary conversion
  • Binary representation of IP addresses and subnet masks
  • Network range calculation with first/last host addresses
  • Support for all standard network classes (A, B, C) and custom subnets