Add, subtract, multiply, divide

Fraction Calculator

Enter two fractions, choose an operation, and see the simplified result with the exact steps.

Calculate fractions

Use whole-number numerators and denominators. The calculator simplifies the final answer.

Important Calculator Notes

This calculator is for educational arithmetic practice and quick fraction checks. It simplifies exact fraction results, but it does not replace your teacher's required method or written work.

Inputs, units, and operations

  • Enter whole-number numerators and denominators for each fraction.
  • Choose addition, subtraction, multiplication, or division before calculating.
  • Denominators cannot be zero, and division by a zero fraction is not valid.
  • The result is reduced to simplest form when possible.

Items not included

  • Mixed-number input, decimal input, variables, radicals, or algebraic fractions.
  • Graphing, number-line visuals, or classroom-specific formatting rules.
  • Interpretation of word problems beyond the fraction operation entered.

For homework, copy the method your class uses and use this result as a check. Different teachers may prefer different intermediate steps even when the final simplified answer is the same.

What is a Fraction?

A fraction represents a part of a whole. The top number is the numerator, which counts the selected parts, and the bottom number is the denominator, which tells how many equal parts make the whole.

Fraction operations are exact, so 1/2 + 1/3 becomes 5/6 rather than a rounded decimal. Simplifying keeps the same value while using smaller equivalent numbers.

How Fraction Operations Are Calculated

Follow these detailed steps:

  1. Step 1: Identify the Operation
    Decide whether you are adding, subtracting, multiplying, or dividing. Addition and subtraction need a common denominator; multiplication and division do not.
  2. Step 2: Apply the Operation Rule
    For addition or subtraction, rewrite both fractions with the same denominator. For multiplication, multiply across. For division, flip the second fraction and multiply.
  3. Step 3: Simplify the Result
    Divide the numerator and denominator by their greatest common divisor so the final fraction is in lowest terms.

Formula

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

Common rules: a/b - c/d = (ad - bc) / bd, a/b x c/d = ac / bd, and a/b รท c/d = ad / bc.

Example

Adding Fractions Example

Problem: Add 1/2 and 1/3. What is the simplified result?

Solution:

  1. First fraction: 1/2, second fraction: 1/3
  2. Common denominator: 2 x 3 = 6
  3. Rewrite: 1/2 = 3/6 and 1/3 = 2/6
  4. Add numerators: 3/6 + 2/6 = 5/6
  5. Result: 5/6 is already simplified

Quick Calculation Tips

Common Mistakes to Avoid

Frequently Asked Questions

Why do addition and subtraction need a common denominator?

The parts must be the same size before you combine them. That is why 1/2 and 1/3 become 3/6 and 2/6.

Does the calculator simplify answers?

Yes. For example, 2/8 is reduced to 1/4 by dividing both numbers by their greatest common divisor.

Can I divide by a fraction?

Yes, unless the second fraction equals zero. Division uses the reciprocal of the second fraction.