Least Common Multiple Calculator

Enter two or more whole numbers, separated by commas, to find their least common multiple.

How to Use the Least Common Multiple Calculator

Same input style as the Greatest Common Factor calculator — comma-separated numbers, any count — just the opposite calculation.

LCM and GCF are two sides of the same factorization, which is why they usually get built as companion tools. The least common multiple of two numbers is their product divided by their GCF:

lcm(a, b) = |a × b| ÷ gcd(a, b)

lcm(4, 6) = 24 ÷ 2 = 12. Dividing by the GCF removes exactly the overlap the two numbers already share, leaving the smallest number both still divide into evenly. This Least Common Multiple Calculator handles two or more numbers the same way GCF does — pairwise, folding each new number into the running result.

The everyday use case is fraction denominators: find the LCM of two denominators and you've got the smallest common denominator to convert both fractions to. It shows up in scheduling too — two buses on different loops, figuring out when they next line up at the same stop.