LCM and GCD Calculator
Greatest common divisor and least common multiple of two numbers.
Frequently Asked Questions
What is the difference between GCD and LCM?
The GCD is the largest number that divides both values exactly. The LCM is the smallest number that both values divide into exactly. For 12 and 18: GCD is 6 and LCM is 36.
How is the GCD calculated?
The calculator uses the Euclidean algorithm: repeatedly replace the larger number with the remainder of dividing the two, until the remainder is zero. The last non-zero value is the GCD, and it is very fast even for huge numbers.
Where are LCM and GCD used?
GCD simplifies fractions to lowest terms. LCM finds common denominators and solves scheduling problems, like two buses departing every 12 and 18 minutes next meeting in 36 minutes.
Is the LCM and GCD Calculator free, and is my data private?
Yes. It is completely free and every calculation runs locally in your browser, so the numbers and dates you enter are never uploaded, stored, or shared with anyone.
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