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GCD and LCM Calculator

Find the greatest common divisor (GCD) and least common multiple (LCM) of two or more whole numbers.

GCD (greatest common divisor)
6
LCM (least common multiple)
180

What is GCD and LCM Calculator?

The greatest common divisor, or GCD, is the largest number that divides all of your numbers without a remainder. The least common multiple, or LCM, is the smallest number that all of them divide into.

They are used to simplify fractions, to add fractions with different bottoms, and to solve scheduling problems.

What this tool does

Takes two or more positive whole numbers and shows their GCD and LCM. It uses the Euclidean algorithm for the GCD and the rule LCM = a ร— b รท GCD for the LCM.

How to use it

  1. Type your numbers, separated by commas or spaces.
  2. Read the GCD and LCM, which update as you type.
  3. Use the GCD to simplify a fraction, or the LCM as a common bottom.

Did you know?

  • The Euclidean algorithm for the GCD is over 2,000 years old and appears in Euclidโ€™s Elements.
  • Two numbers whose GCD is 1 are called coprime, for example 8 and 15.

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