Fraction Calculator
Add, subtract, multiply fractions
About This Calculator
A fraction represents a part of a whole, written as a numerator over a denominator. Fraction arithmetic requires finding common denominators for addition and subtraction, while multiplication and division follow simpler rules. This calculator handles all four operations and returns results in simplest form.
Formula
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)
Always simplify the result by dividing numerator and denominator by their GCD.
Example Calculation
Add 2/3 + 3/4
- Common denominator: 3 × 4 = 12
- 2/3 = 8/12; 3/4 = 9/12
- 8/12 + 9/12 = 17/12
17/12 = 1 5/12
Common Fractions and Decimal Equivalents
| Fraction | Decimal | Fraction | Decimal |
|---|---|---|---|
| 1/2 | 0.5 | 1/5 | 0.2 |
| 1/3 | 0.333 | 2/5 | 0.4 |
| 2/3 | 0.667 | 3/5 | 0.6 |
| 1/4 | 0.25 | 4/5 | 0.8 |
| 3/4 | 0.75 | 1/8 | 0.125 |
| 1/6 | 0.167 | 3/8 | 0.375 |
Frequently Asked Questions
How do I add fractions with different denominators?
Find a common denominator (the LCM of both denominators), convert each fraction, then add the numerators.
How do I divide fractions?
Flip the second fraction (take its reciprocal) and multiply. For example, 2/3 ÷ 4/5 = 2/3 × 5/4 = 10/12 = 5/6.
How do I simplify a fraction?
Divide both the numerator and denominator by their Greatest Common Divisor (GCD). For example, 8/12 — GCD is 4 — gives 2/3.