GCD & LCM Calculator
GCD and LCM calculator: greatest common divisor and least common multiple of two or more whole numbers.
mcm(a, b) = |a · b| / mcd(a, b)
How to use this calculator
- Type your input in the box.
- The result updates as you type.
- Use “Copy result” or “Copy link” to share it.
The GCD is the largest number dividing all of them; the LCM is the smallest number all of them divide. For two numbers, LCM = a·b / GCD.
The LCM gives the common denominator for adding fractions.
Frequently asked questions
GCD and LCM of 12, 18 and 30?
GCD 6, LCM 180.