Least Common Multiple Calculator

Two whole numbers—smallest shared multiple for schedules, gears, and repeat intervals.

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LCM shows up when two rhythms need to line up. Lights blink every 6 seconds and every 8 seconds—when do they sync? A bus every 12 minutes and a train every 18—how long until both depart together from the same clock zero? Enter two integers; the answer is the least common multiple, not the greatest common divisor.

Keep inputs whole unless you have a reason to break them apart elsewhere. Fraction work and percent slices live on other pages.

LCM of 6 and 8 is 24 with the defaults—the kind of result people still list multiples on paper to verify.

Schedules, not magic shortcuts

LCM answers "when cycles coincide," not "how many days between dates." Calendar span questions belong on the date tools. For a quick percent on a budget line, 25% of 80 is unrelated but shows up in the same homework session.

When measurements need unit agreement first, 100 centimeters in inches is a separate check—length, not multiples.

  • Order of the two numbers does not change LCM.
  • Very large inputs can get unwieldy; factor mentally if the UI feels slow.
  • Copy both inputs beside the answer for the worksheet key.

The LCM for schedules note is a light read when word problems hide the repeat. School and planning math, not engineering tolerances.

Results are for informational purposes only. Always double-check important calculations.