Math
Least Common Multiple Calculator
Find the smallest positive number that is a multiple of both of two numbers.
Formula
Least common multiple = (first number × second number) ÷ their greatest common divisor.
How it works
Enter two whole numbers. The calculator first finds their greatest common divisor, then uses it to work out the smallest number both divide into exactly.
FAQs
What does the Least Common Multiple do?
It takes the values you enter and works out the least common multiple for you, showing the result straight away.
What should I enter?
Enter ordinary numbers in the boxes above. If a value does not make sense for this calculation, the page will ask you to check it instead of showing a wrong answer.
Can I use the result for homework or everyday maths?
Yes. It is a general-purpose maths helper; for exam or professional work, still check the steps against your own working.