Fraction Calculator
Add, subtract, multiply, and divide fractions with step-by-step working.
Returns a simplified fraction, mixed number, and decimal with LCM denominator.
A fraction represents a part of a whole. It consists of a numerator (top number) and a denominator (bottom number), separated by a fraction bar. The denominator tells you how many equal parts the whole is divided into; the numerator tells you how many of those parts you have.
Key fraction operations:
Addition/Subtraction — requires a common denominator: 1/3 + 1/4 = 4/12 + 3/12 = 7/12
Multiplication — multiply numerators and denominators straight across: 2/3 × 3/5 = 6/15 = 2/5 (simplified)
Division — multiply by the reciprocal of the divisor: 3/4 ÷ 2/3 = 3/4 × 3/2 = 9/8 = 1 and 1/8
Simplification (reducing): Divide numerator and denominator by their Greatest Common Divisor (GCD). 24/36 → GCD is 12 → 24/12 = 2, 36/12 = 3 → simplified to 2/3
Converting:
- Fraction to decimal: divide numerator by denominator (3/4 = 0.75)
- Decimal to fraction: write as X/1000 then simplify (0.375 = 375/1000 = 3/8)
- Mixed number to improper fraction: (2 and 3/4) = (2×4 + 3)/4 = 11/4
Worked examples:
Baking recipe — halving: Recipe needs 3/4 cup flour. Halving gives 3/4 × 1/2 = 3/8 cup.
Sharing pizza: 5 friends share 3 pizzas equally: 3/5 pizza each.
Why fractions matter: Fractions are exact — unlike decimals, which sometimes round. 1/3 as a decimal is 0.33333… (repeating), never exactly right. Using 1/3 in calculations keeps precision that decimal rounding would lose.
How we build and check this calculator
This calculator runs entirely in your browser, so the numbers you enter stay on your device. The math behind it is written by hand and tested against worked examples and standard references before the page goes live.
SuperGlobalCalculator is independently built and maintained. See how we build and verify our calculators.