Least Common Multiple
Find the smallest positive number that every number in your list divides into evenly. Use it to find a common denominator for fractions or to figure out when repeating events, such as bus schedules, line up again.
- Runs in your browser
- Free, no account needed
- Copy or download the result
Result
Example
4, 6, 10
60
How to use the least common multiple
- Type 2 to 100 whole numbers in the box, such as 4, 6, 10.
- Separate them with commas, spaces, semicolons or new lines.
- Press Run to see the least common multiple.
- Press Copy result or Download to save the answer.
How it works
LCM of two numbers = a x b / GCD(a, b). The tool applies this one number at a time across the list.
Negative numbers are treated by their size, so the result is never negative.
If any number is 0, the result is 0 with a note, since 0 is the only multiple of 0.
Each input can have up to 100 digits. A result longer than 10,000 digits is rejected as too large to display.
The math uses exact big integers, so there is no rounding.
Everything runs in your browser. Your input is not uploaded or stored.
Questions and answers
How do you find the least common multiple?
Multiply the two numbers and divide by their greatest common divisor. For 4 and 6, that is 24 / 2 = 12.
What is the LCM of 4, 6 and 10?
It is 60, the smallest number that 4, 6 and 10 all divide into evenly.
How is the LCM used with fractions?
The LCM of the denominators is the least common denominator. To add 1/4 and 1/6, use 12 as the denominator: 3/12 + 2/12 = 5/12.
What is the difference between LCM and GCD?
The GCD is the largest number that divides all your numbers. The LCM is the smallest number that all your numbers divide into.