The Least Common Multiple (LCM) of a set of integers is the smallest positive integer that is evenly divisible by every number in the set.

How many numbers can I enter?

You can enter between 2 and 10 integers at a time. Each number must be a positive integer between 1 and 10,000,000.

What is the relationship between LCM and GCD?

For two numbers a and b, LCM(a, b) = (a × b) / GCD(a, b). The tool uses the Euclidean algorithm internally to compute GCD, which makes the LCM calculation fast and exact.

Why does entering 1 not change the LCM?

Because 1 divides every integer, it has no effect on the LCM. The LCM of any set that includes 1 is simply the LCM of the remaining numbers.

Can I enter negative numbers?

LCM is defined for positive integers. The tool automatically uses the absolute value of any negative number you enter.

LCM Calculator

Name: LCM Calculator
Availability: InStock
Author: Nham Vu

Enter two or more integers to find their Least Common Multiple (LCM) with a full prime factorization breakdown.

Enter Numbers

Integers (comma or space separated)

Enter 2 to 10 positive integers (max 10,000,000 each).

Quick Examples

Enter integers on the left and click Calculate LCM.

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Summary

Enter two or more integers to find their Least Common Multiple (LCM) with a full prime factorization breakdown.

How it works

Enter two or more integers separated by commas or spaces.
Click "Calculate LCM" to start the computation.
The tool factors each number into its prime components.
It selects the highest power of every prime factor that appears.
The product of those highest powers is the LCM.
A step-by-step breakdown is displayed below the result.

Use cases

Find a common denominator when adding or subtracting fractions.
Determine when two repeating events next occur simultaneously.
Solve homework or exam problems involving multiples.
Verify LCM computations done by hand.
Find the LCM of several numbers at once for engineering tasks.
Understand prime factorization through interactive examples.

Frequently Asked Questions

Last updated: 2026-06-10 · Reviewed by Nham Vu