Mathematical Tools
What It Does
Adds, subtracts, multiplies, and divides fractions exactly, always simplifying the answer and showing it as a fraction, a mixed number, and a decimal — with the steps. It also converts decimals (including repeating ones) to fractions and back. Everything runs in your browser.
How to Use It
- Pick a mode: Calculate, Decimal → Fraction, or Fraction → Decimal.
- Enter fractions as
3/4, whole numbers, or mixed numbers like1 1/2. - Choose an operation (Calculate mode) and read the simplified result and steps.
- Copy any form of the answer.
Options Explained
| Option | Description |
|---|---|
| Mode | Calculate, Decimal → Fraction, or Fraction → Decimal. |
| Operation | Add, subtract, multiply, or divide the two fractions. |
| Result format | Auto (simplest), improper fraction, mixed number, or decimal. |
| Max decimals | How many digits to show for a repeating decimal before marking the cycle. |
| Steps | Show the common-denominator and simplification working. |
1 3/4), and use the repeating notation 0.1(6) to convert a repeating decimal back to its exact fraction.Enter two fractions to calculate an exact result.
About Fractions — Common Denominators, Simplifying & Repeating Decimals
A fraction is just a division that hasn’t been carried out, and the golden rule of fraction arithmetic is that you can only add or subtract fractions that share the same denominator — so 1/4 + 2/3 first becomes 3/12 + 8/12 = 11/12 by rewriting both over their common denominator (here, 12). Multiplying and dividing are easier: multiply straight across, and to divide, flip the second fraction and multiply. Whatever the operation, a good answer is fully simplified — divided top and bottom by their greatest common divisor — so 6/8 becomes 3/4. This tool does all of that with exact whole-number arithmetic (using arbitrary-precision integers), which means it never introduces the rounding errors that plague decimals: 1/3 + 1/6 comes out as exactly 1/2, not 0.4999999. Fractions and decimals are two views of the same number, and the connection is neat: every fraction is either a terminating decimal (when the denominator’s only prime factors are 2 and 5, like 1/8 = 0.125) or a repeating one (like 1/7 = 0.142857…), and every repeating decimal corresponds to an exact fraction — which is why 0.1(6) is precisely 1/6. Everything is computed on your device.