Fraction Calculator
Add, subtract, multiply and divide fractions and mixed numbers, with results simplified automatically.
Fraction Calculator
Add, subtract, multiply and divide fractions and mixed numbers, with results simplified automatically.
How to use the Fraction Calculator
- Enter the first fraction as a/b, a mixed number like 1 1/2, or a decimal like 0.75.
- Select the operation (+, −, ×, or ÷).
- Enter the second fraction.
- Click Calculate.
Formula
a/b + c/d = (ad + bc) / bd
a/b × c/d = ac / bd
a/b ÷ c/d = ad / bc
Example
1/3 + 1/4: Common denominator = 12. (1×4 + 1×3) / 12 = 7/12
Step-by-step calculation
- Find a common denominator: 3 × 4 = 12.
- Convert: 1/3 = 4/12, 1/4 = 3/12.
- Add numerators: 4 + 3 = 7.
- Result: 7/12 (already simplified).
Real-world uses
- Recipe scaling and cooking measurements.
- Construction and engineering measurements.
- Music theory time signatures.
Common mistakes
- Forgetting to simplify the result to lowest terms.
- Treating mixed numbers as multiplication (2 1/3 is not 2 × 1/3).
- Attempting division by a fraction without inverting the divisor.
Frequently asked questions
How do I enter a mixed number?
Type the whole number, a space, then the fraction: "1 1/2" means one and a half.
What does "simplify to lowest terms" mean?
Both numerator and denominator are divided by their greatest common factor. 6/8 simplifies to 3/4.
Can I enter negative fractions?
Yes. Enter negative fractions like -3/4 or -1 2/3.