How do you add fractions with different denominators?

Cross-multiply to get a common denominator: a/b + c/d = (a×d + c×b) / (b×d), then simplify the result.

How do you divide fractions?

Multiply the first fraction by the reciprocal (flipped version) of the second: a/b ÷ c/d = a/b × d/c.

What if the answer is an improper fraction (numerator bigger than denominator)?

That's a valid simplified fraction (e.g. 3/2) — it can also be expressed as a decimal (1.5) or mixed number (1 1/2).

Fraction Calculator

Add, subtract, multiply, or divide two fractions and get the answer automatically simplified to its lowest terms, plus its decimal equivalent.

Numerator

Denominator

Numerator

Denominator

Operation

Result

5/6

≈ 0.8333

How It Works

Adding and subtracting

Fractions are converted to a common denominator (by cross-multiplying) before adding or subtracting the numerators.

Multiplying and dividing

Multiplying fractions multiplies numerators together and denominators together. Dividing multiplies by the second fraction's reciprocal (flip the numerator and denominator, then multiply).

Simplifying

The result is automatically reduced to its simplest form by dividing both the numerator and denominator by their greatest common divisor.

Example Calculation

1/2 + 1/3 = 3/6 + 2/6 = 5/6. Multiplying instead: 1/2 × 1/3 = 1/6.

Common Mistakes

Adding numerators and denominators directly without finding a common denominator first (1/2 + 1/3 is not 2/5).
Forgetting to flip the second fraction when dividing.
Leaving the answer unsimplified — always reduce to lowest terms unless a specific denominator is needed.

Frequently Asked Questions

How do you add fractions with different denominators?: Cross-multiply to get a common denominator: a/b + c/d = (a×d + c×b) / (b×d), then simplify the result.
How do you divide fractions?: Multiply the first fraction by the reciprocal (flipped version) of the second: a/b ÷ c/d = a/b × d/c.
What if the answer is an improper fraction (numerator bigger than denominator)?: That's a valid simplified fraction (e.g. 3/2) — it can also be expressed as a decimal (1.5) or mixed number (1 1/2).