Fraction Calculator

Add, subtract, multiply, or divide fractions with step-by-step working.

First fraction

Second fraction

Try an example

Simplifies automatically · Decimal view · Updated May 2026

Simplified result

1/2 + 1/3 = 5/6

Lowest terms result.

Mixed number

5/6

Useful for improper fractions.

Decimal

0.8333333333

Numerator divided by denominator.

Before simplification

5/6

Raw operation result.

Operation

+

Addition

Step-by-step explanation

  1. 1.Find a common denominator: 2 × 3 = 6
  2. 2.Convert fractions: 1/2 = 3/6, 1/3 = 2/6
  3. 3.Add numerators: 3 + 2 = 5
  4. 4.Result before simplification: 5/6
  5. 5.Already in simplest form: 5/6
1/2 + 1/3 simplifies to 5/6.
As a decimal, the result is 0.8333333333.
The simplified result keeps the numerator and denominator in lowest terms.
Addition and subtraction require a common denominator.
A denominator can never be zero.
Mixed numbers are often easier to read when the result is an improper fraction.

Fraction Formulas

Addition

a/b + c/d = (ad + bc) / bd

Subtraction

a/b − c/d = (ad − bc) / bd

Multiplication

a/b × c/d = ac / bd

Division

a/b ÷ c/d = a/b × d/c

Simplifying

Divide numerator and denominator by the GCD

Decimal form

Decimal = numerator ÷ denominator

Variable Explanations

Numerator

The top number in a fraction.

Denominator

The bottom number that shows the number of equal parts.

GCD

Greatest common divisor used to simplify fractions.

Reciprocal

A flipped fraction, used when dividing fractions.

Improper fraction

A fraction where the numerator is greater than or equal to the denominator.

Mixed number

A whole number plus a fraction.

How Fraction Operations Work

Add

Use a common denominator, then add numerators.

Subtract

Use a common denominator, then subtract numerators.

Multiply

Multiply numerators and denominators across.

Divide

Flip the second fraction, then multiply.

Worked Examples

Add 1/3 + 1/4

Rule: Use a common denominator

Step: 4/12 + 3/12

Answer: 7/12

The common denominator is 12.

Subtract 3/4 − 1/3

Rule: Use a common denominator

Step: 9/12 − 4/12

Answer: 5/12

Subtract only the converted numerators.

Multiply 2/3 × 3/4

Rule: Multiply across

Step: 6/12

Answer: 1/2

Simplify 6/12 by dividing by 6.

Divide 2/3 ÷ 4/5

Rule: Multiply by the reciprocal

Step: 2/3 × 5/4 = 10/12

Answer: 5/6

Flip the second fraction before multiplying.

Convert 7/4 to a mixed number

Rule: Divide numerator by denominator

Step: 7 ÷ 4 = 1 remainder 3

Answer: 1 3/4

The remainder becomes the new numerator.

Convert 3/8 to a decimal

Rule: Divide numerator by denominator

Step: 3 ÷ 8

Answer: 0.375

Decimals are useful for comparisons.

Common Fraction Mistakes

Adding denominators when adding fractions.
Forgetting to find a common denominator for addition or subtraction.
Dividing fractions without flipping the second fraction.
Not simplifying the final result.
Using zero as a denominator.
Losing the negative sign when simplifying.
Confusing improper fractions with mixed numbers.
Rounding the decimal too early.

Understanding Your Result

Simplified fraction

The answer in lowest terms.

Mixed number

A readable form for improper fractions.

Decimal

The numerator divided by the denominator.

Raw result

The fraction before simplification.

Step-by-step work

Shows how the answer was calculated.

Frequently Asked Questions