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

What if one number is zero?

GCF(a, 0) = |a|. We treat negative inputs as their absolute value for the result.

Online GCF Calculator

Find the Greatest Common Factor (GCF), also called GCD, of two integers. GCF is the largest positive integer that divides both numbers.

First integer

Second integer

What is GCF?: The Greatest Common Factor (or GCD) of two integers is the largest positive integer that divides both without remainder.
What if one number is zero?: GCF(a, 0) = |a|. We treat negative inputs as their absolute value for the result.

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