Subnet Calculator by LOCHOTIN IP Calculator

Network Class

First Octet Range

IP Address

Hex IP Address

Subnet Mask

Wildcard Mask

Subnet Bits

Mask Bits

Maximum Subnets

Hosts per Subnet

Host Address Range

Subnet ID

Broadcast Address

Subnet Bitmap

IP Calculator Overview

The IP Calculator on ip-calc.com is ideal for classful IP calculations using network class, IP address, subnet mask, subnet bits, mask bits, and the maximum number of subnets and hosts required.

Calculation Results

Instant results include:

  • Hexadecimal IP Address
  • Wildcard Mask (for ACL configurations)
  • Subnet ID
  • Broadcast Address
  • Subnet Address Range
  • Subnet Bitmap

All you need for classful networks.

Additional Resources

You want Classless? - use our CIDR IP Calculator.

Building Access Control Lists? - We've got you covered with our Wildcard Mask Calculator.


IPv4 Subnetting: From Classful to Classless (A Down-to-Earth History and Explanation)

  1. The subnet calculator implements a classful / classed IP addressing scheme where the following rules are adhered to:

    • Class A addresses have their first octet in the range 1 to 126 (binary address begins with 0).

    • Class B addresses have their first octet in the range 128 to 191 (binary address begins with 10).

    • Class C addresses have their first octet in the range 192 to 223 (binary address begins with 110).

  2. The subnet calculator allows the use of a single subnet bit - for example, a class C address with a subnet mask of 255.255.255.128 is permitted.

  3. The subnet calculator allows a subnet ID to have its final octet equal to the final octet of its subnet mask - for example, a class C network address of 192.168.0.192 with a subnet mask of 255.255.255.192 is permitted.

The above is generally accepted as being 'normal', however, certification students should keep in mind that, in some certification programs, the final two points are regarded as inacceptible.

For classless subnetting, you can use the CIDR calculator.

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