Fraction Calculator

All tools

Add, subtract, multiply or divide two fractions and instantly get the simplified result, plus its decimal, mixed-number and percentage forms. Free and instant.

+
Result –
As decimal –
As mixed number –
As percentage –
Results are reduced to lowest terms using the greatest common divisor. Division by a zero denominator is undefined.

About Fraction Calculator

The Fraction Calculator adds, subtracts, multiplies or divides two fractions and returns the simplified result. Alongside the reduced fraction you get the answer as a decimal, as a mixed number and as a percentage — four views of the same value.

Addition and subtraction convert both fractions to a common denominator before combining numerators; multiplication multiplies straight across; division multiplies by the reciprocal of the second fraction. Every result is reduced to lowest terms using the greatest common divisor, and division by a zero denominator is flagged as undefined.

It is a reliable check for homework, recipe scaling, woodworking measurements or anywhere fractions appear and mental arithmetic gets risky. Free and instant, computed in your browser.

How to use Fraction Calculator

  1. Choose the operation: add, subtract, multiply or divide.
  2. Enter the numerator and denominator of Fraction A.
  3. Enter the numerator and denominator of Fraction B.
  4. Read the simplified result, plus its decimal, mixed-number and percentage forms.

Frequently asked questions

Rewrite both over a common denominator, then add the numerators: 1/3 + 1/4 = 4/12 + 3/12 = 7/12. The calculator does the conversion and then reduces the answer to lowest terms.

Multiply by the reciprocal: a/b ÷ c/d = a/b × d/c. So 3/4 ÷ 2/5 = 3/4 × 5/2 = 15/8, shown as the mixed number 1 7/8 and the decimal 1.875.

The numerator and denominator are divided by their greatest common divisor (GCD). 8/12 has a GCD of 4, so it reduces to 2/3 — the lowest-terms form the calculator always displays.

A whole number combined with a proper fraction, like 1 3/4 instead of the improper fraction 7/4. The calculator shows both, since improper fractions suit further math while mixed numbers read naturally.

A denominator of zero makes a fraction undefined — division by zero has no value. Check that both denominators are non-zero, and that you are not dividing by a fraction equal to zero.
Share this
Related Tools
Percentage Calculator Answer every percentage question — X% of Y, what percent, percentage change, increase/decrease, tips and discounts. Free, in your browser. Free
Scientific Calculator A full scientific calculator with trigonometry, logarithms, powers, roots, factorials, memory and history — in degrees or radians. Free, in your browser. Free
Text to Binary, Octal & Hex Convert text to binary, octal, decimal and hexadecimal — and back again. Every field is live and editable, with delimiter, padding and uppercase options. Free
Average Calculator Paste a list of numbers to instantly get the mean, median, mode, range, sum, count and more. Robust parsing handles commas, spaces and new lines. Free and instant. Free
Standard Deviation Calculator Enter a data set to compute the sample and population standard deviation, variance and mean. Robust parsing handles commas, spaces and new lines. Free and instant. Free
Aspect Ratio Calculator Work out the aspect ratio of any width and height, resize a picture or video while locking its ratio, or pick a preset like 16:9, 4:3 or 21:9. Also solves any proportion A:B = C:D and simplifies ratios — with decimals, megapixels and orientation. Free and instant. Free
Need help?
Found an issue with this tool? Let our team know.
Report an issue

Add this free tool to your own website — copy and paste the code below.