The Fraction Calculator performs arithmetic operations with fractions — addition, subtraction, multiplication, and division. It also simplifies fractions to their lowest terms and converts between fractions, decimals, and mixed numbers.
How the Formula Works
Addition: a/b + c/d = (ad + bc) / bd. Subtraction: a/b − c/d = (ad − bc) / bd. Multiplication: a/b × c/d = ac / bd. Division: a/b ÷ c/d = ad / bc.
Finding LCD (Least Common Denominator): LCM of the two denominators
Simplifying: Divide both numerator and denominator by their GCD
Mixed to improper: whole × denominator + numerator, over denominator
Improper to mixed: Divide numerator by denominator; remainder is new numerator
How to Use This Calculator
Enter the first fraction (numerator and denominator)
Select the operation (+, −, ×, ÷)
Enter the second fraction
View the result in simplified form, as a decimal, and as a mixed number
Tips & Best Practices
To divide fractions, flip the second fraction and multiply ('keep, change, flip')
Always simplify your answer by dividing by the GCD of the numerator and denominator
When adding fractions with different denominators, find the LCD first
Any whole number can be written as a fraction with 1 as the denominator (e.g., 5 = 5/1)
Important Limitations
Some fractions produce repeating decimals (1/3 = 0.333...) that cannot be expressed exactly in decimal form
Very large numerators or denominators may lose precision in decimal conversion