Fraction Calculator

Fraction Calculator does fraction sums the way you were taught to do them on paper, and shows every line. Type two fractions or mixed numbers, pick + − × or ÷, and the answer appears as a simplified fraction, a mixed number, a decimal and a percentage. Underneath, the working finds the lowest common denominator, rewrites both fractions, combines the tops and simplifies by the greatest common divisor, so a student can check their own method rather than just copy an answer.

For longer sums, the Expression tab reads a whole line such as 1 1/2 + 3/4 × (2/5 − 1/10) and follows the order of operations: brackets, powers, then × and ÷, then + and −. Three smaller tabs cover the jobs that usually need separate sites: Simplify shows Euclid’s method for the GCD, Decimal → fraction converts repeating decimals like 0.1(6) using the algebra trick from school, and Compare puts a list of fractions in order with a shared denominator and bars to show their sizes.

All the maths is exact. Numbers are stored as whole-number pairs of any length, so nothing is rounded until the decimal line, and repeating decimals are found by long division rather than guessed. It runs entirely in your browser.

1. In “Two fractions”, type the top and bottom of each fraction. For a mixed number, also fill the dashed “whole” box on the left.
2. Tap +, −, × or ÷ between them (or type the symbol while in a box). Use ± to make a fraction negative.
3. Read the answer card: fraction, mixed number, decimal and percent, each with its own copy button.
4. Follow “Step-by-step working”, or press “Copy working” to paste it into your notes.
5. For anything longer, open “Expression” and type the whole sum; “Simplify”, “Decimal → fraction” and “Compare” sit in the tabs alongside.

• Two-fraction mode with separate whole, top and bottom boxes, drawn as a real stacked fraction.
• Answers as a simplified fraction, mixed number, exact decimal with a repeat bar (1.1(6)) and percent.
• Working for every operation: improper fractions, lowest common denominator, flip-and-multiply for division, GCD simplifying and the remainder for mixed numbers.
• Expression mode with brackets, powers (^), mixed numbers and decimals, using order of operations and showing each operation in turn.
• Simplify tab with Euclid’s algorithm written out, plus equivalent fractions.
• Decimal → fraction for ending and repeating decimals (0.(3), 0.1666…, 2.(142857)) and percentages.
• Compare tab that sorts up to 30 fractions, shows them over a common denominator and draws a bar for each.
• Exact whole-number maths of any size, “Use answer as first” for chained sums, and keyboard shortcuts for the operations.

• In a mixed number the minus sign goes on the whole number: −1 1/2 means minus one and a half, not −1 + 1/2.
• In the Expression tab, 3/4 written between two whole numbers is treated as one fraction, so 1/2 ÷ 3/4 gives 2/3 as a teacher would expect.
• If your homework wants the answer “in lowest terms”, the Fraction line is already fully simplified.
• A decimal that ends is any fraction whose bottom number, once simplified, has only 2s and 5s as factors. Anything else repeats.
• Typing 0.333… tells the tool to work out the repeat itself; brackets such as 0.(3) are clearer when the repeating block is long.