Math Calculators
LCM Calculator
Find the least common multiple.
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About the LCM Calculator
The least common multiple (LCM) is the smallest number that two or more integers all divide into evenly. Enter two or three numbers and the calculator returns their LCM. It's the key to adding fractions with different denominators and solving many number-theory and scheduling problems.
How to use the LCM Calculator
- 01Enter your two or three numbers.
- 02Read the result instantly — it recalculates as you type.
- 03Adjust the numbers to model different scenarios.
Frequently asked questions
What is the LCM?
The smallest positive number that all the given numbers divide into evenly — the least common multiple.
How do I find the LCM?
LCM(a, b) = a × b ÷ GCF(a, b). This tool uses that relationship, which extends to more numbers.