What is the difference between GCD and LCM?

The GCD (greatest common divisor, also called HCF) is the largest whole number that divides all of your numbers exactly. The LCM (least common multiple) is the smallest whole number that all of them divide into exactly.

Can I enter more than two numbers?

Yes. Enter as many whole numbers as you like, separated by commas or spaces, and the calculator finds the GCD and LCM across all of them.

Is anything sent to a server?

No — the calculation runs entirely in your browser using the Euclidean algorithm, and nothing you type is ever uploaded.

GCD & LCM Calculator

Find the greatest common divisor and least common multiple of any numbers.

GCD & LCM calculator

Find the greatest common divisor (GCD) and least common multiple (LCM) of any set of whole numbers. The GCD — also called the highest common factor (HCF) — is the largest number that divides every value exactly. The LCM is the smallest number that every value divides into.

Enter two or more numbers, separated by commas or spaces, and both results update instantly. Everything runs in your browser, so nothing you enter is uploaded.