Fraction Calculator

Add, subtract, multiply, and divide two fractions instantly with our free fraction calculator. Enter numerators and denominators to get the simplified result, mixed number, and decimal value automatically.

How to Use

  1. Enter the first fraction

    Input the numerator and denominator of the first fraction.

  2. Select operation and enter second fraction

    Choose addition, subtraction, multiplication, or division, then enter the second fraction.

  3. View result

    Click Calculate to see the simplified result and its decimal equivalent.

What is a fraction?

A fraction expresses part of a whole as numerator/denominator. The denominator shows how many equal parts the whole is divided into, and the numerator shows how many of those parts you have. For example, 3/4 means 3 out of 4 equal parts of the whole.

Fractions let you represent quantities that don't divide evenly by 1 with perfect accuracy. A value that would repeat forever as a decimal, like 0.333..., can be handled cleanly as 1/3. That's why fractions are essential in cooking recipes, dividing lengths and time, probability, and school mathematics.

This calculator performs addition, subtraction, multiplication, and division of two fractions, automatically simplifies the result to lowest terms, and also shows the mixed number and decimal value.

Calculation formulas

The four arithmetic operations for two fractions a/b and c/d are as follows.

  • Addition: a/b + c/d = (ad + cb) / bd
  • Subtraction: a/b - c/d = (ad - cb) / bd
  • Multiplication: a/b × c/d = ac / bd
  • Division: a/b ÷ c/d = ad / bc (multiply by the reciprocal of the second fraction)

Here b and d are the denominators, and a and c are the numerators. For example, 1/2 + 1/3 = (1×3 + 1×2) / (2×3) = 5/6. Finally, divide the numerator and denominator by their greatest common divisor (GCD) to simplify (e.g., 4/8 has a GCD of 4, giving 1/2).

Frequently Asked Questions

How do I add fractions?
Fractions with different denominators must share a common denominator first. Compute a/b + c/d = (ad + cb) / bd, then simplify by the greatest common divisor (GCD). Example: 1/2 + 1/3 = (3 + 2) / 6 = 5/6.
How do multiplication and division of fractions differ?
To multiply fractions, multiply numerator by numerator and denominator by denominator (a/b × c/d = ac/bd). To divide, flip the second fraction and multiply (a/b ÷ c/d = ad/bc). This calculator simplifies the result automatically in both cases.
What does simplifying a fraction mean?
Simplifying means dividing the numerator and denominator by their greatest common divisor (GCD) to reach the lowest terms. Example: the GCD of 4/8 is 4, so 4/8 = 1/2.
Can it handle mixed numbers?
A mixed number combines a whole number with a proper fraction (e.g., 7/3 = 2 1/3). When the numerator exceeds the denominator, it is automatically converted to an improper fraction for the calculation, and the result is shown as both a mixed number and an improper fraction.
Are results simplified automatically?
Yes, the result is always converted to its simplest form (one that cannot be reduced further) and displayed automatically. No separate simplification step is needed.
Can I convert a fraction to a decimal?
Yes, the result is shown as a fraction together with its decimal representation at the same time. The decimal value is rounded to 6 decimal places.
Can a fraction with a denominator of 0 be calculated?
A fraction with a denominator of 0 is mathematically undefined. If you enter 0 as a denominator, no calculation is performed; the same applies when the numerator of the second fraction is 0 in division (division by zero).
Can I enter negative fractions?
Yes, entering a negative numerator calculates a negative fraction. The sign of the result is always placed on the numerator (e.g., a negative denominator is auto-corrected), so you can read the sign consistently.
Verified 2026 formulas

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