GCD and LCM Calculator
Find the greatest common divisor and least common multiple of a list of whole numbers.
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How to use GCD and LCM Calculator
Euclid’s algorithm finds the greatest common divisor. The least common multiple is accumulated using |a ÷ gcd(a,b) × b| with exact BigInt arithmetic.
- Enter whole numbers.
- Check that the input follows the stated limits and uses consistent units.
- Run the calculator, review the result, then copy or download it.
Good to know
- Up to 100 whole numbers with magnitude at most 1 trillion. Signs are ignored. The LCM is zero if any input is zero; gcd(0,0) is reported as zero.
- Decimal inputs have at most 120 characters and magnitude from 1e-100 to 1e15, or zero. Floating-point results are rounded to 12 significant digits; extreme derived results may underflow or be rejected. Exact integer results are identified separately.
Common questions
What calculation does GCD and LCM Calculator perform?
Euclid’s algorithm finds the greatest common divisor. The least common multiple is accumulated using |a ÷ gcd(a,b) × b| with exact BigInt arithmetic.
Can the output exceed the input limit?
Yes. Exact BigInt output can be much larger than the input values, while list length keeps the work bounded.
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