Greatest Common Factor (GCF) Calculator

Enter two or more integers separated by commas to find their Greatest Common Factor (GCF), also called the GCD.

How to Find the GCF

Method: Euclidean Algorithm

  1. Divide the larger number by the smaller number.
  2. Replace the larger number with the remainder.
  3. Repeat until the remainder is 0. The last non-zero remainder is the GCF.

Example: GCF(48, 18)

  • 48 = 2 × 18 + 12
  • 18 = 1 × 12 + 6
  • 12 = 2 × 6 + 0 → GCF = 6

GCF & LCM Relationship

GCF(a, b) × LCM(a, b) = a × b

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