GCD & LCM Calculator
Find the greatest common divisor (HCF) and least common multiple of two or more numbers, with steps.
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How to use
- Type two or more whole numbers separated by commas or spaces.
- The GCD and LCM appear instantly.
- For two numbers, open the step-by-step working to see Euclid’s algorithm.
How it works
The GCD is found with Euclid’s algorithm, which repeatedly replaces the larger number with the remainder of dividing it by the smaller one. The LCM is then |a × b| ÷ GCD. Whole numbers of any size are handled exactly.
Limitations
- Up to 100 numbers at once.
Privacy
Your text is processed entirely in this browser tab. Nothing is uploaded, logged or saved by this tool.
Local processing protects your data from being uploaded, but it cannot protect against a compromised device or malicious browser extensions.