GCD and HCF Calculator Online

Find the greatest common divisor (GCD) or highest common factor (HCF) of two numbers.

First number

Second number

GCD and HCF calculator

GCD (greatest common divisor) and HCF (highest common factor) mean the same thing: the largest positive integer that divides both numbers. We use the Euclidean algorithm to compute it.

Frequently Asked Questions

What is GCD or HCF?

GCD (greatest common divisor) and HCF (highest common factor) are the same: the largest positive integer that divides both numbers with no remainder.

How do you find GCD?

The Euclidean algorithm: repeatedly replace the larger number by its remainder when divided by the smaller until one is 0; the other is the GCD.

LCM Calculator →Denominator Calculator →

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