Summary
A fraction calculator does arithmetic with fractions and gives the answer as a simplified fraction. To use this one free and privately, type the First fraction, press Add, Subtract, Multiply or Divide, type the Second fraction, and read the Result. It appears as a mixed number, an improper fraction and a decimal, with a Step-by-Step Solution underneath. The calculation runs in your browser and nothing is uploaded.
To add or subtract, rewrite both fractions over their lowest common denominator. To multiply, multiply the numerators and the denominators. To divide, multiply by the reciprocal of the second fraction. Then divide top and bottom by their greatest common divisor. For example, 1/2 + 1/3 = 3/6 + 2/6 = 5/6. For percentages use the percentage calculator, and for powers and roots the scientific calculator.
Table of Use: Example Calculations
Each row was run through the calculator itself and is shown as it displays.
| Situation | What you enter | What it shows |
|---|---|---|
| Add unlike fractions | 1/2, Add, 1/3 | 5/6 ≈ 0.8333333333, via the common denominator 6 |
| Subtract | 3/4, Subtract, 1/6 | 7/12 ≈ 0.5833333333 |
| Multiply and simplify | 2/3, Multiply, 3/4 | 6/12 simplified by 6 to 1/2 = 0.5 |
| Divide | 2/3, Divide, 1/2 | 1 1/3 = 4/3 ≈ 1.3333333333 |
| Mixed numbers | whole 2, 1/2, Add, whole 1, 3/4 | 4 1/4 = 17/4 = 4.25 |
| Negative mixed number | whole −2, 1/3, Multiply, 3/5 | −1 2/5 = −7/5 = −1.4 |
| Scaling a recipe | 3/4, Multiply, whole 2, 1/2 | 1 7/8 = 15/8 = 1.875 |
| Decimal to Fraction | Decimal number 2.125 | 17/8 = 2 1/8 as a mixed number |
| Rounded decimal | Decimal number 0.333 | 333/1000; closest simple fraction (denominator up to 100): 1/3 |
Features
- Four operations on two fractions or mixed numbers, including negative values.
- Every result in lowest terms, as a mixed number, an improper fraction and a decimal that is marked = when exact and ≈ when rounded to 10 places.
- Step-by-Step Solution that can be hidden, covering the common denominator, the operation and the simplifying divisor.
- Visual Comparison: pie charts for both fractions and a >, < or = sign comparing the first with the second.
- Quick Simplify for your two input fractions, and a Common Fractions list of nine everyday fractions with decimals.
- Decimal to Fraction gives the exact fraction, a mixed number, and a closest simple fraction when the exact one is large.
- Exact arithmetic for up to 15 digits in each box, plus a Copy Result button for the mixed-number form.
Know the limits: it handles two fractions at a time, and the fraction boxes take whole numbers only, so enter decimals in the Decimal to Fraction box. For unit conversions such as fractions of an inch, use the length converter.
How to Use the Fraction Calculator
- In First fraction, type the numerator and denominator. Add a number in whole for a mixed number, or only a whole number for an integer.
- Press Add, Subtract, Multiply or Divide (the +, −, × and ÷ buttons).
- Fill in the Second fraction the same way.
- Read the Result, press Copy Result to copy it, and use Show Step-by-Step Solution or Hide Step-by-Step Solution to toggle the working.
- For a decimal, type it into Decimal number under Decimal to Fraction.
Results update as you type. Nothing is uploaded; the Network tab in DevTools will show no request.
Who Can Use It
Students can check homework against the steps, and teachers can generate worked examples. Cooks can scale a recipe, and makers can add up measurements. For ingredient amounts in other units try the weight converter, or the unit converter's Volume category for cups and millilitres; to find how much a tin or box holds, use the volume calculator.
Fractions turn up in marks too: a score such as 17/20 can be entered as points in the grade calculator, or as 85% on the Percentage scale of the GPA calculator. For one third off, enter 33.3333 in the discount calculator, and to find the area of a board or panel measured in inches, use the area calculator.
FAQs
How do I add fractions with different denominators?
Rewrite both fractions over their lowest common denominator, then add the numerators. For 1/2 + 1/3 the common denominator is 6, so 3/6 + 2/6 = 5/6. In the calculator choose Add, enter both fractions and read the Result; the Step-by-Step Solution lists the common denominator, the rewritten fractions and any simplifying.
How do I enter a mixed number or a negative fraction?
Type the whole number in the whole box and the fraction in the numerator and denominator boxes, so 2 1/2 is whole 2, numerator 1, denominator 2. For a negative mixed number put the minus sign on the whole number: −2 1/3 means −7/3. For a negative simple fraction leave whole empty and put the minus sign on the numerator.
How do you divide fractions?
Multiply the first fraction by the reciprocal of the second, which is the second fraction flipped: 2/3 ÷ 1/2 = 2/3 × 2/1 = 4/3 = 1 1/3. Dividing by zero is undefined, so if the second fraction equals 0 the calculator shows a message instead of a result.
How do I simplify a fraction to lowest terms?
Divide the numerator and denominator by their greatest common divisor. For 12/18 the divisor is 6, so 12/18 = 2/3. Every result is already in lowest terms, and Quick Simplify shows each of your two input fractions in lowest terms too: type 12 and 18 in the First fraction and it displays 2/3.
How do I convert a decimal to a fraction?
Write the decimal over a power of ten and simplify: 0.75 = 75/100 = 3/4, and 2.125 = 2125/1000 = 17/8 = 2 1/8. The Decimal to Fraction box does this exactly. For 0.333 the exact answer is 333/1000, and it also offers the closest simple fraction with a denominator up to 100, which is 1/3.
Why does the decimal show ≈ instead of =?
A fraction in lowest terms has a terminating decimal only if its denominator has no prime factors other than 2 and 5. 3/8 = 0.375 is exact, but 1/3 repeats, so it shows ≈ 0.3333333333. The decimal is rounded half up to 10 places, so 2/3 shows ≈ 0.6666666667, and 1/2048 shows ≈ 0.0004882813 because its exact decimal, 0.00048828125, needs 11 places.
Is my data sent anywhere?
No. The arithmetic runs in your browser, using exact whole-number maths that stays precise for up to 15 digits in each box, and nothing you type is uploaded. You can confirm it by opening the Network tab in DevTools and changing a number: no request is made.