Math & Algebra
GCD & LCM Calculator
Two positive integers.
Educational estimates only. Not medical, legal, tax, or financial advice.
Guide: GCD & LCM Calculator
What it does
Uses number theory algorithms to find GCD and LCM.
How to use it
Enter integers separated as the form specifies, then calculate.
Formula
gcd(a,b) via Euclidean algorithm; lcm(a,b) = |ab|/gcd(a,b); extend to lists.
Example
gcd(84, 30) = 6; lcm(12, 18) = 36.
FAQs
Do negative numbers work?
GCD/LCM are usually defined on absolute values of integers.
More than two numbers?
gcd(a,b,c)=gcd(gcd(a,b),c); lcm extends similarly.
Zero as input?
gcd(n,0) is often defined as |n|; lcm with zero is problematic—check inputs.