Does a negative input change the answer?
No. Divisibility uses the absolute values, so the sign does not affect the GCD or LCM.
GCD & LCM Calculator
Find the greatest common divisor and least common multiple of two integers.
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Adjust the values below to get a clear estimate.
Euclidean algorithm and product relation
Repeated remainders find the GCD efficiently. For non-zero values, the LCM is the absolute product divided by the GCD; zero is handled directly.
gcd(a,b) = gcd(b, a mod b); lcm(a,b) = |ab| / gcd(a,b)Worked example
A shared divisor pair
Inputs: firstNumber: 48 · secondNumber: 18
Illustrative result: GCD 6 · LCM 144
Six is the largest shared divisor; 48 × 18 divided by 6 gives the least common multiple 144.
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Frequently asked questions
What is the LCM when one input is zero?
By this calculator’s convention, it is zero because zero is divisible by every non-zero integer multiple relationship used here.