The Greatest Common Factor (GCF) of two integers is the largest positive integer that divides both without remainder.

What if one number is zero?

GCF(a, 0) = |a|. We use absolute values for the result.

Online GCF Calculator

Find the Greatest Common Factor (GCF) of two integers. Same as GCD — the largest positive integer that divides both.

First integer

Second integer

What is GCF?: The Greatest Common Factor (GCF) of two integers is the largest positive integer that divides both without remainder.
What if one number is zero?: GCF(a, 0) = |a|. We use absolute values for the result.

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