Math Calculators
GCF Calculator
Find the greatest common factor.
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About the GCF Calculator
The greatest common factor (GCF), also called the greatest common divisor, is the largest number that divides two or more integers evenly. Enter two or three numbers and the calculator returns their GCF using the Euclidean algorithm. It's essential for simplifying fractions and factoring.
How to use the GCF Calculator
- 01Enter your two or three numbers.
- 02Read the result instantly — it recalculates as you type.
- 03Adjust the numbers to model different scenarios.
Frequently asked questions
What is the GCF?
The largest positive integer that divides all the given numbers with no remainder — the greatest common factor (or divisor).
How is GCF used?
To simplify fractions (divide numerator and denominator by the GCF) and to factor expressions. The tool also pairs with the LCM Calculator.