Free app

Fraction Calculator

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Enter two fractions and an operation. Results are automatically reduced to lowest terms.

Result

5/6

5/6 · 0.8333333333333334

How It Works

Fraction arithmetic follows fixed rules depending on the operation. To add or subtract, you need a common denominator: multiply each fraction so both share the same bottom number (a/b ± c/d = (a·d ± c·b) / (b·d)), then combine the numerators. To multiply, simply multiply the numerators together and the denominators together (a/b × c/d = ac/bd). To divide, multiply the first fraction by the reciprocal (flip) of the second (a/b ÷ c/d = a/b × d/c = ad/bc). After any operation, the result is reduced to its lowest terms by dividing the numerator and denominator by their greatest common divisor. This calculator applies the correct rule for your chosen operation and presents the answer three ways — as a simplified fraction, as a mixed number (whole part plus a proper fraction), and as a decimal — so it fits whatever form you need.

Formula

Add/Subtract: a/b ± c/d = (ad ± cb)/bd. Multiply: (a/b)(c/d) = ac/bd. Divide: (a/b)÷(c/d) = ad/bc. Then reduce by the GCD.

Frequently Asked Questions

How do I add two fractions?

Give them a common denominator, then add the numerators: a/b + c/d = (a·d + c·b) / (b·d). For example, 1/2 + 1/3 = (3 + 2)/6 = 5/6. The calculator also reduces the result automatically.

How do I divide fractions?

Multiply the first fraction by the reciprocal (flip) of the second: (a/b) ÷ (c/d) = a/b × d/c. For example, 1/2 ÷ 1/4 = 1/2 × 4/1 = 4/2 = 2.

What is a mixed number?

A whole number combined with a proper fraction, like 1 1/2. An improper fraction such as 3/2 equals the mixed number 1 1/2. The calculator shows both forms.

How are results simplified?

The numerator and denominator are divided by their greatest common divisor (GCD) to reduce the fraction to lowest terms — so 4/8 becomes 1/2 automatically.

Can I multiply fractions without a common denominator?

Yes — multiplication and division do not need a common denominator (only addition and subtraction do). To multiply, just multiply across: numerators together and denominators together.