Fraction Calculator

Add, subtract, multiply and divide fractions with simplified results.

How to add, subtract, multiply and divide fractions

• Add or subtract: a/b ± c/d = (a×d ± c×b) ÷ (b×d)
• Multiply: a/b × c/d = (a×c) ÷ (b×d)
• Divide: a/b ÷ c/d = (a×d) ÷ (b×c). In other words, multiply by the reciprocal of the second fraction.

The answer is then simplified by dividing the top and bottom by their greatest common divisor.

Worked examples

• 1/2 + 1/3: (1×3 + 1×2) ÷ (2×3) = 5/6, or 0.8333 as a decimal.
• 3/4 − 1/6: (3×6 − 1×4) ÷ (4×6) = 14/24, which simplifies to 7/12.
• 2/3 × 3/5: 6/15, which simplifies to 2/5.
• 1/2 ÷ 3/4: (1×4) ÷ (2×3) = 4/6, which simplifies to 2/3.
• Mixed number: 7/4 is 1 and 3/4.

Frequently asked questions

How do I simplify a fraction?

Divide the numerator and denominator by their greatest common divisor. For 14/24, both divide by 2, giving 7/12.

How do I add fractions with different denominators?

Convert them to a common denominator, then add the numerators. The calculator uses the product of the denominators, then simplifies the result.

Can I use mixed numbers?

Convert them first. 1 1/2 becomes 3/2 (1 × 2 + 1 = 3 over 2). The result is also shown as a mixed number when it is greater than 1.

What if a denominator is zero?

A fraction with a zero denominator is undefined, so the calculator shows a message instead of a result.