LCM Calculator

Find the least common multiple (LCM) of two integers instantly—a crucial step when adding fractions, aligning repeating schedules, or sizing gear teeth.

Enter any whole number; decimals are rounded down to the nearest integer.
Use positive or negative values—the calculator converts to absolute integers automatically.

Educational tool. Double-check results when building safety-critical schedules or mechanical systems.

Examples

  • LCM(48, 180) ⇒ 720, the shared cycle for synchronized maintenance intervals
  • LCM(12, 18) ⇒ 36, helpful when finding a common denominator
  • LCM(7, 5) ⇒ 35, the first meeting of two independent weekly tasks

FAQ

How is the LCM calculated?

We compute gcd(a, b) using the Euclidean algorithm and return |a × b| ÷ gcd(a, b).

Can I paste fractional values?

Yes. The calculator strips decimals by flooring the values, effectively using the integer portion.

What about negative inputs?

Negatives are converted to their absolute values so the final LCM is always non-negative.

How do I handle three or more numbers?

Compute LCM pairwise—for example LCM(LCM(a, b), c)—or use a multi-number LCM formula in a spreadsheet.

Additional Information

  • Uses the greatest common divisor (Euclidean algorithm) to compute LCM efficiently, even for large integers.
  • If either input is zero the result is zero, because no positive multiple exists that both numbers share.
  • Extend the method to more numbers by iteratively computing LCM(result, next value).

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