GCF & LCM Calculator

Calculate the Greatest Common Factor (GCF) and Least Common Multiple (LCM) of two or more numbers simultaneously.

Enter two or more numbers separated by commas.

Formulas

GCF: The largest number that divides all given numbers evenly.
LCM: The smallest number that is a multiple of all given numbers.
Relationship: GCF(a, b) × LCM(a, b) = a × b
Example: Numbers: 12, 18, 24
GCF(12, 18, 24) = 6
LCM(12, 18, 24) = 72

Methods to Find GCF and LCM

  • Prime Factorization: Factor each number into primes. GCF uses lowest powers; LCM uses highest powers.
  • Euclidean Algorithm: Repeatedly apply division to find GCF. Use the relationship GCF × LCM = product for LCM.

Last updated: 2026-08-08