This page contains a fractions calculator. Enter two fractions and choose whether to add, subtract, multiple, or divide the fractions. We'll perform your choice of math and let the tool return you the simplest fraction form.
Fractions Arithmetic Calculator
What are Fractions?
Fractions are two numbers expressed as a part of a whole. They consist of a top number (numerator) and a bottom number (denominator) and imply division.
Fraction Arithmetic
For the four basic arithmetic functions – addition, subtraction, division, and multiplication – there are basic rules to follow when working with fractions. I'll walk you through each one and show an example.
Adding Fractions
To add two fractions:
- First, convert both fractions to a common base by multiplying top and bottom by the same number to equal a base. (You can find the least common denominator, or lazily multiply all denominators together).
- Add the two numerators, and place the result in a new numerator.
- Add the two denominators and place the result in a new denominator.
- (Optional) Find the reduced or simplest form of the fraction.
Example Fraction Addition
Let's add two fractions together: 3/9 and 1/7.
Subtracting Fractions
To subtract two fractions:
- First, convert both fractions to a common base. You then need to multiply top and bottom numbers by the same number to equal a base. (Either find the least common denominator, or simply multiply the denominators together).
- Subtract the second numerator from the first, placing the result in a new numerator.
- Subtract the second denominator from the first, placing the result in a new denominator.
- (Optional) Find the reduced or simplest fraction form.
Example Fraction Subtraction
Let's subtract the fraction 1/7 from 6/21.
Multiplying Fractions
Multiplying two fractions is the easiest one to remember – just multiply the numerator and denominator across:
- Multiply the first numerator by the second and put it in a new numerator.
- Multiply the first denominator by the second and put it in a new denominator.
- (Optional) Find the reduced or simplest fraction form.
Example Fraction Multiplication
Let's multiply the fractions 3/9 and 1/7.
Dividing Fractions
Dividing fractions is also relatively straightforward. We add one step to multiplication and invert or "flip" the second fraction.
- Rewrite the second fraction to take its inverse, or put the denominator over the numerator.
- Multiply the first numerator by the new numerator of the rewritten second and put it in a third numerator.
- Multiply the first denominator by the new denominator of the rewritten second and put it in a third denominator.
- (Optional) Find the reduced or simplest fraction form.
Example Fraction Division
Let's divide the fraction 1/7 by 1/3.
How to Use the Fractions Calculator
You can use the fractions calculator without remembering all those arithmetic functions!
In the box for Fraction One, enter the numerator for the first fraction. In the box for Fraction Two, enter the numerator and denominator of the second fraction.
In the Operation menu, choose which function to perform – do you want to add (+), subtract (-), multiply (*) or divide (÷) the fractions? Choose your preference from the menu. Then hit the Perform Fractional Math button.
The automatically simplified answer will be listed in the Result box.
