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Calcimator

LCM Calculator

Calculate the Least Common Multiple (LCM) of two or more numbers. Uses prime factorization to find the smallest number that is a multiple of all inputs.

Inputs

Results

Least Common Multiple (LCM)

36

Greatest Common Divisor (GCD)6
Numbers Calculated2
LCM Prime Factorization2^2 × 3^2
Calculation StepsStep 1: Find prime factorization of each number • 12 = 2^2 × 3 • 18 = 2 × 3^2 Step 2: Take highest power of each prime factor LCM = 2^2 × 3^2 = 36
How to Use This Calculator
  1. Enter two required integers and up to two optional additional integers in the Number fields.
  2. The Least Common Multiple is the smallest positive integer divisible by all entered numbers, computed as LCM(a,b) = |a × b| / GCD(a,b).
  3. LCM is essential when adding or subtracting fractions with unlike denominators — the LCM becomes the common denominator.
  4. For more than two numbers the calculator applies LCM iteratively: LCM(a,b,c) = LCM(LCM(a,b),c).
  5. Leave optional number fields at 0 to exclude them from the calculation.
  6. All inputs must be positive integers; the LCM of any number and 0 is undefined.
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Formula

LCM(a, b) = |a × b| / GCD(a, b)

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