About the GCD and LCM Calculator
Find the greatest common divisor and least common multiple of two numbers. This tool is free, works in your browser and needs no sign-up.
How to use the GCD and LCM Calculator
Enter two whole numbers.
Formula used
GCD is found with the Euclidean algorithm. LCM = a × b ÷ GCD.
Example
For 12 and 18 the GCD is 6 and the LCM is 36.
Frequently asked questions
Is the GCD and LCM Calculator free to use?
Yes. It is completely free and you can use it as many times as you like.
How accurate is the GCD and LCM Calculator?
The calculator uses standard formulas, so the maths is exact. Real life results can differ because of fees, taxes, rounding or personal factors, so treat the answer as an estimate.
Do you store the numbers I enter?
No. All calculations run in your browser. The values you type are not sent to our server.
Disclaimer: results are estimates for information only. They are not financial, medical or professional advice.