GCD & LCM Calculator

Find the greatest common divisor and least common multiple of two or more numbers using the Euclidean algorithm. Free online GCD & LCM calculator.

Frequently Asked Questions

What is the relationship between GCD and LCM?
For two numbers a and b, GCD(a,b) x LCM(a,b) = a x b. This means you can derive one from the other if you know the product of the two numbers.
Can I calculate GCD and LCM for more than two numbers?
Yes, enter multiple numbers separated by commas and the calculator will find the GCD and LCM of the entire set.
What is the Euclidean algorithm?
The Euclidean algorithm finds the GCD by repeatedly dividing the larger number by the smaller and taking the remainder, until the remainder is zero.
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