GCD and LCM Calculator
GCD and LCM Calculator: Find the exact greatest common divisor and least common multiple of two integers.
GCD and LCM Calculator
GCD and LCM Calculator: Enter two whole numbers. The calculator uses exact integer arithmetic to compute the greatest common divisor and least common multiple.
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How to use GCD and LCM Calculator
Enter two whole numbers. The calculator uses exact integer arithmetic to compute the greatest common divisor and least common multiple.
How GCD and LCM Calculator calculates the result
The greatest common divisor is the largest positive integer that divides both inputs. For nonzero inputs, least common multiple = |a × b| ÷ GCD(a,b). The zero cases need separate handling.
Example
For 12 and 18, the GCD is 6 and the LCM is 36.
What to know
Values are limited to 150 digits each. The pair 0, 0 is undefined; one zero and one nonzero value has LCM zero.