HCF & LCM Calculator

This is a demonstration of how to find the highest common factor (HCF or GCD) and the lowest common multiple (LCM) of two numbers.

Before starting you need to know your times tables and the divisibility tests.

Example 1. Find the HCF and LCM of 72 and 96:

Show Example 1

You can vary the speed using this slider:







Practise finding the highest common factor (H.C.F), sometimes called the greatest common divisor, and the lowest common multiple (L.C.M) of two numbers.

The short web address is:


HCF & LCM Calculator

Transum subscribers are able to choose their own numbers for this calculator. They are able to type their two numbers into a form which appears here and see the highest common factor and lowest common multiple being revealed above.

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This method is sometimes known as the Indian Method

Many people know the highest common factor as the greatest common divisor and use the abbreviation GCD instead of HCF.


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