Fraction Calculator — Add, Subtract, Multiply, Divide
Enter two values — proper fractions (`3/4`), mixed numbers (`1 1/2`), whole numbers (`5`), or decimals (`1.25`) — pick an operation, and get the exact result. The answer is shown as a fully reduced fraction, an equivalent mixed number, and a decimal, plus the step-by-step work: finding a common denominator for addition and subtraction, multiplying across for products, and inverting the divisor for division. All math uses exact BigInt arithmetic, so there's no floating-point rounding, and everything runs in your browser.
Accepts fractions (3/4), mixed numbers (1 1/2), whole numbers (5), and decimals (1.25).
Result
17/12
Simplified
17/12
Mixed number
1 5/12
Decimal
1.4166666667
Steps
3/4 + 2/3 = 9/12 + 8/12 = 17/12 = 17/12 = 1 5/12
Exact BigInt arithmetic — results are fully reduced. The decimal is rounded for display only.
How to use
- Type a fraction in each field: 3/4, a mixed number like 1 1/2, a whole number, or a decimal like 1.25.
- Choose +, −, ×, or ÷ for the operation.
- Read the reduced result, the mixed-number form, and the decimal — and expand the steps to see how it was solved.
- Copy the result line with the copy button.
Frequently asked questions
- What input formats are accepted?
- Proper or improper fractions (3/4, 7/4), mixed numbers with a space (1 1/2), whole numbers (5), and decimals (1.25). Negative signs go in front: -3/4 or -1 1/2.
- Is the result always fully reduced?
- Yes. After every operation the fraction is divided by the greatest common divisor of numerator and denominator, so 8/12 is shown as 2/3.
- Are the answers exact?
- Yes — the calculator works with BigInt integers internally, so there's no floating-point error. The decimal field is rounded for display, but the fraction and mixed-number forms are exact.
- How is a decimal turned into a fraction?
- 1.25 becomes 125/100, which reduces to 5/4. The number of decimal places sets the power-of-ten denominator before reducing.
- What happens if I divide by zero?
- Dividing by a fraction that equals zero is undefined, so the calculator shows an error instead of a result.
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