Math

Fraction Calculator

Add, subtract, multiply, or divide fractions with reduced and decimal results.

Inputs

Results update as you edit.

First numerator

First denominator

Operation

Second numerator

Second denominator

Reduced result

23/20

Results update as the calculator inputs change.

Decimal

1.15

Mixed number

1 3/20

Unreduced result

23/20

How to Calculate Fractions

Numerator and Denominator

A fraction compares a numerator to a nonzero denominator.

Operation

Addition, subtraction, multiplication, and division follow fraction arithmetic rules.

Reduced Result

The final fraction is simplified using a common divisor.

How Fraction Arithmetic Works

Fraction calculations keep values exact by using numerators and denominators. Addition and subtraction need common denominators, while multiplication and division use direct numerator-denominator rules.

What Affects Fraction Results?

Denominator

A denominator cannot be zero and controls the size of each part.

Common Denominator

Addition and subtraction convert fractions to a shared denominator first.

Multiplication

Multiplication combines numerators and denominators directly.

Division

Dividing by a fraction multiplies by its reciprocal.

Reduction

Simplifying divides numerator and denominator by their greatest common divisor.

Decimal Form

Decimals are convenient but can round repeating fractions.

Common Fraction Uses

Exact Arithmetic

Keep measurements or ratios exact before converting to decimals.

Simplifying

Reduce final answers for easier reading.

Decimal Conversion

Compare the exact fraction with its decimal approximation.

Frequently Asked Questions

How do you add fractions?

Convert them to a common denominator, add the numerators, then reduce the result.

How do you multiply fractions?

Multiply numerator by numerator and denominator by denominator, then simplify.

How do you divide fractions?

Multiply the first fraction by the reciprocal of the second fraction.

Why can't the denominator be zero?

Division by zero is undefined, so a fraction with zero denominator is invalid.

Why is my decimal rounded?

Some fractions repeat forever in decimal form, so the calculator displays a rounded decimal.