GCD Calculator (Greatest Common Divisor)
Enter two or more whole numbers to find their greatest common divisor (also called the GCF or HCF). The calculator folds the Euclidean algorithm across your whole list.
How to find the greatest common divisor
- Type your integers separated by commas or spaces.
- Read the GCD, the largest number that divides every value evenly.
- Copy the result or add more numbers to recompute instantly.
Examples
GCD of two numbers
48, 36
12
GCD of a longer list
12, 18, 24
6
Frequently asked questions
What is the greatest common divisor?
The greatest common divisor (GCD) of a set of integers is the largest positive integer that divides every one of them with no remainder.
Is the GCD the same as the GCF or HCF?
Yes. Greatest common divisor (GCD), greatest common factor (GCF), and highest common factor (HCF) are three names for the same value.
How does the calculator handle negative numbers?
It uses absolute values, so the GCD of -48 and 36 is 12. A divisor is always reported as a positive integer.
What is the GCD when one number is zero?
The GCD of 0 and 5 is 5, because every integer divides 0. The GCD of all zeros is defined here as 0.
Why must the inputs be whole numbers?
The greatest common divisor is only defined for integers. The tool rejects decimals or non-numeric text so the answer stays exact.
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