IP address and subnet calculator - IP Calculator

Online calculator of IP addresses and subnets for IPv4 and IPv6. Calculate the network, first and last IP, CIDR and number of hosts. Support for reverse range calculation.

1000+
Networks
99%
Calculation accuracy
IPv4/IPv6
Data Format

Calculation of IP and subnets

Calculate network parameters, IP range and number of hosts

About the IP and subnet calculator

Online calculator of IP addresses and subnets for IPv4 and IPv6. Calculate the network, first and last IP, CIDR and number of hosts. Support for reverse range calculation. All network addressing parameters are taken into account.

Examples of using the calculator

Subnet calculation using CIDR

For example, need to calculate the parameters of the network 192.168.1.0/24

The calculator will determine: subnet mask 255.255.255.0, number of hosts 254, first IP 192.168.1.1, last IP 192.168.1.254, broadcast address 192.168.1.255

The network can contain 254 hosts with addresses from 192.168.1.1 to 192.168.1.254

Subnetting

For example, you need to divide the 10.0.0.0/16 network into 4 subnets

The calculator will create subnets: 10.0.0.0/18, 10.0.64.0/18, 10.0.128.0/18, 10.0.192.0/18

Each subnet can contain up to 16,382 hosts

Reverse range calculation

For example, you need to find the CIDR for the range from 172.16.0.1 to 172.16.255.254

The calculator will determine: network 172.16.0.0/16, mask 255.255.0.0, number of hosts 65,534

The range corresponds to network 172.16.0.0/16

Working with IPv6

For example, you need to calculate the subnet 2001:db8::/64

The calculator will determine: prefix 2001:db8::, prefix length 64, number of addresses 2^64

A subnet can contain 18,446,744,073,709,551,616 addresses

Determining network parameters

For example, you need to define network parameters for IP 203.0.113.42/28

The calculator will determine: network 203.0.113.32, mask 255.255.255.240, first IP 203.0.113.33, last IP 203.0.113.46, broadcast 203.0.113.47

The network contains 14 hosts with addresses from 203.0.113.33 to 203.0.113.46

How IP and Subnets are Calculated

The calculator uses standard network calculation formulas:

  • Network address: IP & mask
  • Number of hosts: 2^(32-CIDR) - 2
  • Range: network + 1 to broadcast - 1

Basic functions

Basic functions

Calculation of IPv4 networks

Full calculation of IPv4 subnet parameters

Calculation of IPv6 networks

Support for modern IPv6 addresses

CIDR notation

Working with CIDR notation for accurate calculations

Reverse calculation

Determining CIDR by IP Range

Preview

Graphical representation of a subnet

Export results

Saving results to PDF or Excel

Benefits of the calculator

Our IP calculator provides many benefits for network calculations.

Accurate calculations

Uses current network addressing standards

Flexible settings

Supports various input formats

Full analysis

Accounting for all network addressing parameters

Export data

Ability to save results in PDF or Excel

Frequently Asked Questions

How to calculate a subnet by IP and mask?

Network address = IP & mask, number of hosts = 2^(32-CIDR) - 2.

What is CIDR and how to use it?

CIDR shows the number of bits in the subnet mask, for example /24 means 255.255.255.0.

How to determine the first and last IP on the network?

First IP = network address + 1, last IP = broadcast address - 1.

How to calculate the number of available hosts?

Number of hosts = 2^(32-CIDR) - 2 for IPv4, 2^(128-CIDR) for IPv6.

Can this calculator be used for IPv6?

Yes, the calculator supports both IPv4 and IPv6 addresses.