Math calculator
GCD & LCM Calculator
Find the greatest common divisor and least common multiple.
About the gcd & lcm calculator
The GCD & LCM calculator finds the greatest common divisor and least common multiple of two numbers.
How to use this calculator
- 1
Enter two numbers
Enter two positive integers.
- 2
View results
See the GCD and LCM.
How the calculation works
GCD via Euclidean algorithm. LCM = (a × b) ÷ GCD.
Example: GCD(12, 18) = 6. LCM(12, 18) = 36.
When to use a calculator vs. mental math
Simple operations like percentages and proportions are great for mental math. Complex problems — quadratic equations, standard deviation, and base conversions — benefit from calculator precision. Always estimate the answer first to catch input errors, and verify results with a second method when possible.
Important limitations
This tool provides a mathematical estimate based only on the values entered. It does not account for regulations, taxes, lender fees, market conditions, or individual circumstances. Results are for planning purposes only — consult a qualified professional for regulated, medical, financial, or construction decisions.
Frequently asked questions about gcd & lcm calculator
How accurate is the GCD LCM calculator?+
The calculation follows the displayed formula and retains full numeric precision before formatting the result.
Can I use the result professionally?+
Use it as a planning estimate. Confirm regulated, medical, financial, or construction decisions with a qualified professional.