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LCM & GCD Calculator

Find the LCM and GCD (HCF) of a set of integers.

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Understanding your result

The GCD is the largest number dividing all inputs; the LCM is the smallest number they all divide into.

Formula and method

GCD is found with the Euclidean algorithm; LCM(a, b) = |a × b| ÷ GCD(a, b), extended across all numbers.

Worked example

For 12 and 18, the GCD is 6 and the LCM is 36.

How to use this tool

  1. Enter integers separated by commas or spaces.
  2. Read the LCM and GCD.

Common mistakes to avoid

  • Including non-integers or zero.

About the LCM & GCD Calculator

Find the least common multiple (LCM) and greatest common divisor (GCD / HCF) of two or more integers.

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Frequently asked questions

Is GCF the same as GCD?

Yes. GCF (greatest common factor) and HCF are other names for the GCD.