LCM & GCF Calculator

Least common multiple and greatest common factor of any numbers.

Quick answer: Calculate Least Common Multiple (LCM) and Greatest Common Factor (GCF) online. Math tool for reducing fractions and solving ratios.

LCM180
GCF / HCF6

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Find the least common multiple and greatest common factor (also called HCF) of two or more whole numbers at once.

How it works

  1. Enter a list of two or more whole numbers.
  2. The engine uses Euclid's algorithm to extract common primes.
  3. View the lowest common multiple and highest common factor instantly.

Frequently asked questions

Where is LCM used in real life?

Common denominators for fractions, aligning repeating schedules, and gear/cycle problems.

GCF vs HCF — different things?

Same concept, different names: greatest common factor (US) = highest common factor (UK/India).

Why whole numbers only?

LCM/GCF are defined on integers. For decimals, scale them to integers first (×10, ×100…).

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