Fraction Calculator
Type two fractions, mixed numbers or decimals, pick the operation, and see the answer in lowest terms with each step of the working. What you type stays in your browser.
Type fractions like 3/4, mixed numbers like 1 1/2 (with a space), whole numbers or decimals.
Steps
Fraction sums with every step shown
Fractions turn up in recipes, measurements, woodwork and homework, and the method is easy to forget: common denominators, turning a fraction upside down to divide, simplifying at the end. This calculator does the sum and shows each step, so you can check an answer or relearn the method. Numbers of any length work, and every answer is exact.
How to use it
- Type the first number: a fraction like 3/4, a mixed number like 1 1/2 (with a space), a whole number or a decimal.
- Pick add, subtract, multiply or divide, and type the second number.
- Read the answer in lowest terms, as a mixed number and as a decimal, with the steps below it.
- To turn a decimal into a fraction, use the box underneath.
How the steps work
- Adding and subtracting: both fractions are rewritten over the least common multiple of their denominators, then the numerators are added or subtracted.
- Multiplying: the numerators are multiplied together, and so are the denominators.
- Dividing: the second fraction is turned upside down, then the two are multiplied.
- Simplifying: the top and bottom are divided by their greatest common divisor, which leaves the fraction in lowest terms.
Repeating decimals
Some fractions never end as decimals: 1/3 is 0.333… forever. The calculator writes the repeating part in brackets, so 1/3 is 0.(3), 1/6 is 0.1(6) and 1/7 is 0.(142857). The decimal box reads the same notation: type 0.(3) and you get 1/3. Typed without brackets, 0.333 means exactly 333/1000, and the tool points that out.
Good to know
- Negative numbers: put the minus sign in front, as in −3/4 or −1 1/2. The sign belongs to the whole mixed number.
- Exact, however long: the arithmetic uses whole numbers with no rounding. Only a very long repeating decimal is cut off after 100 places, and the tool says so.
- Decimals in a sum: 0.5 + 1/4 works, because each decimal is first written as a fraction over 10, 100 or 1,000.
- Mixed answers: an answer bigger than 1 is also shown as a mixed number, so 13/6 appears as 2 1/6 too.
- Zero: a denominator of 0, or dividing by 0, gets a clear message.
- Private: nothing you type is sent or saved.
Teaching fractions? The Lesson Plan Generator lays out a lesson with timed steps.