lcm(4, 6)
= 12
Twelve is the first positive multiple shared by four and six.
Least Common Multiple Calculator
Calculate the exact LCM of large whole numbers. Find common multiples and repeating cycle lengths.
How this calculation works
For nonzero inputs, the least common multiple is the smallest positive integer divisible by both. It is related to the GCD by LCM(a, b) = |a × b| / GCD(a, b).
Inputs and accuracy
Both inputs must represent whole numbers. Signs are ignored in the returned magnitude. When either input is zero, this calculator returns zero rather than a positive common multiple.
When to use it
Find common denominators for fractions or the time when two integer-period cycles coincide, provided both cycles start at the same reference point.
Worked examples
lcm(21, 6)
= 42
Shared factors keep the LCM smaller than the product.
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