Fraction Calculator

Add, subtract, multiply, or divide two fractions. See the result as a simplified fraction, a decimal, and a mixed number.

Examples

1/2 + 1/4

Add a half and a quarter

Numerator 1
1 none
Denominator 1
2 none
Operation
Add (+)
Numerator 2
1 none
Denominator 2
4 none
Decimal value
0.75
Numerator (simplified)
3
Denominator (simplified)
4
Mixed number
3/4

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How It Works

Formula

ab+cd=ad+cbbd\frac{a}{b} + \frac{c}{d} = \frac{a \cdot d + c \cdot b}{b \cdot d}

abcd=adcbbd\frac{a}{b} - \frac{c}{d} = \frac{a \cdot d - c \cdot b}{b \cdot d}

ab×cd=acbd\frac{a}{b} \times \frac{c}{d} = \frac{a \cdot c}{b \cdot d}

ab÷cd=adbc\frac{a}{b} \div \frac{c}{d} = \frac{a \cdot d}{b \cdot c}

Variables, symbols and units

aa

Numerator of the first fraction

bb

Denominator of the first fraction

cc

Numerator of the second fraction

dd

Denominator of the second fraction
Calculation method explained

Enter two fractions and pick an operation. The calculator combines them with the standard rule for that operation, then divides numerator and denominator by their greatest common divisor (GCD) to give the simplest form. Sign stays on the numerator; the denominator is always positive.

Examples

1/2 + 1/41 none · 2 none0.75

Add a half and a quarter

Numerator 1
1 none
Denominator 1
2 none
Operation
Add (+)
Numerator 2
1 none
Denominator 2
4 none
Decimal value
0.75
3/4 × 2/33 none · 4 none0.5

Multiply two proper fractions

Numerator 1
3 none
Denominator 1
4 none
Operation
Multiply (×)
Numerator 2
2 none
Denominator 2
3 none
Decimal value
0.5
5/6 − 1/35 none · 6 none0.5

Subtract with a common denominator

Numerator 1
5 none
Denominator 1
6 none
Operation
Subtract (−)
Numerator 2
1 none
Denominator 2
3 none
Decimal value
0.5

Frequently Asked Questions

What is a proper vs improper fraction?
A proper fraction has |numerator| smaller than the denominator (e.g. 3/4). An improper fraction has |numerator| ≥ denominator (e.g. 5/4). Improper fractions can be rewritten as a mixed number, like 1 1/4.
Why simplify the result?
Simplifying divides numerator and denominator by their greatest common divisor (GCD), giving the smallest equivalent form. 6/8 simplifies to 3/4 — same value, easier to read.
How do I convert a decimal to a fraction?
Write the decimal as a fraction over a power of 10 (0.75 = 75/100), then simplify by dividing top and bottom by their GCD (75/100 = 3/4).
How do I add fractions with different denominators?
Find a common denominator (the product of the two works, then simplify). Multiply each numerator by the other denominator and add: a/b + c/d = (a·d + c·b) / (b·d).
What are common mistakes when multiplying fractions?
A typical mistake is finding a common denominator first — you do not need one to multiply. Just multiply numerators together and denominators together, then simplify.

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