What does "simplify" mean?

Simplify means reducing a fraction to its lowest terms so the numerator and denominator share no common factor.

Yes. It is free, runs in your browser, and no data is uploaded.

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Fraction Calculator

Add, subtract, multiply and divide fractions and get a simplified answer — instantly and privately.

Operation

First numerator

First denominator

Second numerator

Second denominator

What is a fraction calculator?

A fraction calculator performs arithmetic on fractions — the numbers written as one value over another, like 1/2, where the top number is the numerator and the bottom is the denominator. It handles all four operations: adding, subtracting, multiplying and dividing. For addition and subtraction it puts the two fractions over a common denominator before combining them; for multiplication it multiplies the numerators and denominators straight across; and for division it flips the second fraction and multiplies. The tool then simplifies the answer to its lowest terms using the greatest common divisor, and converts a result with a denominator of one into a whole number. Fractions are essential wherever you split a whole into equal parts — cooking recipes, woodworking measurements, ratios, part-whole comparisons and pretty much any maths beyond whole numbers. This calculator makes those operations instant and gives you the simplified fraction plus the working, and it runs entirely in your browser.

Example

To add 1/2 + 1/3, put them over a common denominator of 6 to get 3/6 + 2/6 = 5/6. The calculator returns 5/6, already in its simplest form, along with the step it used.

Who is this Fraction Calculator for?

Anyone who needs to add, subtract, multiply or divide fractions and see the answer simplified — students, teachers, college learners and professionals all use it for the same reason.

Students: add and subtract fractions with different denominators, simplify answers to lowest terms and check homework or classwork.
Teachers: create worked examples, show a common denominator step by step and demonstrate how to reduce a fraction by its greatest common divisor.
College students: work with fractions inside algebra, calculus and statistics parts of a course, including ratios and part-whole problems.
Professionals: scale recipes, measure in woodworking or sewing, and handle the fractional measurements common in DIY and engineering.

Fractions at a glance

Each row shows the result in simple fractional form and as a decimal, produced by the same rules this calculator applies.

Expression	Result	Decimal
1/2 + 1/3	5/6	0.8333
1/2 − 1/4	1/4	0.25
2/3 × 3/4	1/2	0.5
1/2 ÷ 1/4	2	2
3/4 ÷ 1/2	3/2	1.5
6/8 simplified	3/4	0.75

Because you multiply the top and bottom by the same amount, the equivalent fractions of 1/2 are 2/4, 3/6, 4/8 and 5/10 — all the same value.

Common use cases

Checking homework or classwork and verifying that you simplified the answer correctly.
Scaling a recipe up or down by doubling or halving the ingredient amounts.
Working with measurements in woodworking, sewing or DIY where fractions are common.
Solving part-whole problems and ratios in finance, statistics or everyday maths.

Pro tips

Dividing by zero is undefined — a fraction with a zero denominator cannot be evaluated, and the tool flags this.
Always reduce the final answer to its simplest form by dividing top and bottom by their greatest common divisor.
To divide fractions, flip the second fraction (take its reciprocal) and multiply instead.
Check an answer with cross-multiplication or a decimal conversion to be sure it is correct.

How to use

Enter the numerator and denominator of the first fraction.
Choose an operation (add, subtract, multiply or divide).
Enter the second fraction and click Calculate to see the simplified result.

Formula

a/b + c/d = (a·d + c·b) / (b·d)\na/b − c/d = (a·d − c·b) / (b·d)\na/b × c/d = (a·c) / (b·d)\na/b ÷ c/d = (a·d) / (b·c)\nThen divide numerator & denominator by their GCD.

FAQ

How do you add two fractions?

Find a common denominator, then add the numerators and simplify. For example, 1/2 + 1/3 = 3/6 + 2/6 = 5/6.

What does "simplified" mean?

It means the fraction is reduced to lowest terms so the numerator and denominator share no common factor.

How do you divide fractions?

Multiply the first fraction by the reciprocal of the second. For example, 3/4 ÷ 1/2 = 3/4 × 2/1 = 3/2.

How do I add fractions?

Put both fractions over a common denominator, add the numerators, and keep the denominator. Then simplify if possible.

What is a common denominator?

A shared multiple of both denominators. It lets you combine fractions by giving them the same bottom number.

How do I divide fractions?

Flip the second fraction to its reciprocal and multiply. For example, 1/2 ÷ 1/4 becomes 1/2 × 4/1 = 2.

How do you simplify a fraction?

Divide the numerator and denominator by their greatest common divisor to get the lowest terms.

Can it handle mixed numbers?

You can convert a mixed number to an improper fraction first, then use the calculator with the numerator and denominator.

What happens if the denominator is zero?

A fraction with a zero denominator is undefined, so the calculator refuses to compute it and shows an error.