Fraction Calculator
Add, subtract, multiply, and divide two fractions. The answer is reduced to lowest terms and shown as a mixed number and a decimal. Calculates in your browser.
Result
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Show the math
Fractions are combined over a common denominator, then reduced by their greatest common divisor:
a/b + c/d = (a·d + c·b) / (b·d)
a/b − c/d = (a·d − c·b) / (b·d)
a/b × c/d = (a·c) / (b·d)
a/b ÷ c/d = (a·d) / (b·c)
The answer is always shown in lowest terms, with the mixed-number and decimal forms beneath it.
What this does
A fraction calculator adds, subtracts, multiplies, and divides two fractions. The answer is reduced to lowest terms and shown as a mixed number and a decimal, so you can read it whichever way suits the task.
How to use it
- Enter the numerator and denominator of each fraction.
- Choose add, subtract, multiply, or divide.
- Read the reduced result, mixed number, and decimal.
How it works
Addition and subtraction put both fractions over a common denominator, then combine the numerators. Multiplication goes straight across; division multiplies by the reciprocal of the second fraction. The result is then reduced.
a/b ± c/d = (a·d ± c·b) ÷ (b·d)
Understanding your result
The answer is always reduced to lowest terms, so 2/4 comes back as 1/2, the same value in simplest form. The fraction, mixed-number, and decimal views are one result shown three ways, pick whichever the task needs. A decimal that does not terminate, like 1/3 shown as 0.333, is rounded for display only, the fraction itself stays exact, so prefer the fraction when precision matters.
Example
1/2 + 1/3 = 5/6. And 3/4 ÷ 1/2 = 3/2, which the tool also shows as the mixed number 1 1/2 and the decimal 1.5.
Sources & methodology
Last updated .
Frequently asked questions
How do you add or subtract fractions?
Put both over a common denominator, then add or subtract the numerators: a/b ± c/d = (a·d ± c·b) ÷ (b·d). The result is then reduced.
How do you multiply and divide fractions?
Multiply straight across (a/b × c/d = a·c ÷ b·d). To divide, multiply by the reciprocal of the second fraction (a/b ÷ c/d = a·d ÷ b·c).
What is a mixed number?
It is a whole number plus a proper fraction, like 3 1/2 instead of 7/2. The tool shows the mixed form whenever the answer is an improper fraction.
Is my data stored?
No. Everything is calculated locally in your browser.
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