Fraction Calculator

Add, subtract, multiply, and divide fractions — simplified instantly with steps

Fraction 1
Fraction 2
Common examples
Result
Decimal
Unsimplified
GCD Used
Mixed Number

Fraction Formulas Explained

Add / Subtract: a/b ± c/d = (a×d ± c×b) / (b×d)
Example: 1/2 + 1/3 = (1×3 + 1×2) / (2×3) = 5/6
Multiply: a/b × c/d = (a×c) / (b×d)
Example: 2/3 × 3/5 = 6/15 = 2/5
Divide: a/b ÷ c/d = a/b × d/c = (a×d) / (b×c)
Example: 1/2 ÷ 3/4 = 1/2 × 4/3 = 4/6 = 2/3
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Always simplify: after any operation, divide the numerator and denominator by their greatest common divisor (GCD) to get the simplest form.

Common Fraction Operations Reference

OperationUnsimplifiedSimplifiedDecimal
1/2 + 1/35/65/60.8333
1/2 + 1/46/83/40.75
3/4 − 1/85/85/80.625
2/3 − 1/31/31/30.3333
2/3 × 3/56/152/50.4
1/2 × 1/21/41/40.25
1/2 ÷ 3/44/62/30.6667
3/4 ÷ 1/26/43/21.5

Frequently Asked Questions

How do you add fractions with different denominators?

Find a common denominator (multiply the two denominators, or use their LCM), convert each fraction, then add the numerators. Example: 1/2 + 1/3 = 3/6 + 2/6 = 5/6.

How do you subtract fractions?

Convert both fractions to a common denominator, then subtract the numerators and keep the denominator. Example: 3/4 − 1/8 = 6/8 − 1/8 = 5/8.

How do you multiply fractions?

Multiply the numerators together and the denominators together, then simplify. Example: 2/3 × 3/5 = 6/15 = 2/5.

How do you divide fractions?

Multiply the first fraction by the reciprocal (flip) of the second. Example: 1/2 ÷ 3/4 = 1/2 × 4/3 = 4/6 = 2/3.

What is 1/2 + 1/3?

1/2 + 1/3 = 5/6. Common denominator is 6: 1/2 = 3/6 and 1/3 = 2/6, so 3/6 + 2/6 = 5/6, already in simplest form.

What is 3/4 minus 1/8?

3/4 − 1/8 = 5/8. Convert 3/4 to eighths: 6/8. Then 6/8 − 1/8 = 5/8.

How do you simplify a fraction?

Find the greatest common divisor (GCD) of the numerator and denominator, then divide both by it. Example: 6/15 — GCD(6,15)=3, so 6÷3 / 15÷3 = 2/5.

How do you convert an improper fraction to a mixed number?

Divide the numerator by the denominator. The quotient is the whole number; the remainder over the original denominator is the fraction part. Example: 11/4 = 2 remainder 3, so 11/4 = 2 3/4.

Can you add fractions with negative numerators?

Yes. Treat the negative sign as part of the numerator and follow the same common-denominator process. Example: −1/2 + 1/4 = −2/4 + 1/4 = −1/4.

What is a common denominator?

A shared multiple of two or more denominators that lets fractions be added or subtracted directly. The easiest one is the product of both denominators; the LCM gives smaller numbers.

Why do you flip the second fraction when dividing?

Dividing by a fraction equals multiplying by its reciprocal, since a/b ÷ c/d = a/b × d/c. Flipping the divisor turns division into easier-to-compute multiplication.

What is 2/3 times 3/5?

2/3 × 3/5 = 6/15, which simplifies to 2/5 by dividing both numbers by their GCD of 3.

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