Sumivo · Mathematics

LCM Calculator

Find the least common multiple of two or more integers — the smallest positive number they all divide into.

01 / inputs

integers

02 / result

LEAST COMMON MULTIPLE

24

LCM
24
GCD
2
Count
3

Calculation trace

  1. lcm(4, 6) = 4 × 6 ÷ gcd(2) = 12
    12
    LCM step 1
  2. lcm(12, 8) = 12 × 8 ÷ gcd(4) = 24
    24
    LCM step 2
§

How it works

The least common multiple (LCM) is the smallest positive integer that every input divides into with no remainder. The tool folds the list two at a time using lcm(a, b) = |a × b| ÷ gcd(a, b), where the greatest common divisor gcd(a, b) is found with the Euclidean algorithm; for three or more numbers, lcm(a, b, c) = lcm(lcm(a, b), c).

Assumptions & limits

  • Inputs must be non-zero integers; decimals and zero are rejected.
  • A negative sign is ignored — a number and its negation have the same LCM.
  • Results above 2^53 may lose exact integer precision, and a warning is shown.
§

FAQ

What is the least common multiple?
The smallest positive integer that each of your numbers divides into evenly. For 4 and 6 the LCM is 12.
How is the LCM related to the GCD?
They satisfy lcm(a, b) × gcd(a, b) = |a × b|, so the LCM equals the product of two numbers divided by their greatest common divisor.
Why can’t the LCM include zero?
Zero has no positive multiples in common with other numbers, so the least common multiple involving 0 is undefined.
What is the LCM used for?
Adding or comparing fractions with different denominators, finding when repeating events line up again, and gear or timing problems all rely on the LCM.
§

Related calculators

§

SOURCES

  • OpenStax, Rice University
    Prealgebra 2e

    Least common multiple: listing multiples and prime factorization

    Accessed 2026-09-02