GCD & LCM Calculator
Compute the greatest common divisor and least common multiple of two or more positive integers using the Euclidean algorithm. Everything runs in your browser.
Enter two or more positive integers
FAQ
Can it handle more than two numbers?
Yes—enter any count separated by commas or spaces; GCD and LCM are folded across the list.
How are GCD and LCM related?
For two numbers, a × b = GCD × LCM. The tool computes LCM as (a ÷ GCD) × b to avoid overflow.
Does it work with huge numbers?
If the LCM exceeds the safe integer range (2⁵³−1), the result is withheld to avoid inaccuracy.
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