MultiConvers

Fraction Calculator

Add, subtract, multiply or divide two fractions written as whole-number tops and bottoms, then see the reduced form, a mixed number and a decimal.

How to use

  1. Enter the first numerator and denominator, then the second.
  2. Pick add, subtract, multiply or divide.
  3. Read the simplified fraction. Improper answers also appear as mixed numbers.
  4. Convert a mixed input yourself first: 1 1/2 is 3/2. Use Fraction to Decimal if you only have one pair.

How it works

School fraction arithmetic is four operations on two rational numbers. Addition and subtraction need a common denominator: 1/2 + 1/3 = 3/6 + 2/6 = 5/6. Multiplication is tops together and bottoms together: 2/3 × 3/4 = 6/12, which reduces to 1/2. Division multiplies by the reciprocal: 1/2 ÷ 1/4 = 1/2 × 4/1 = 2.

Dividing by 0/n or by a zero numerator on the right is undefined. A zero denominator on either side is rejected. The page never prints Infinity.

Results are reduced by the GCF so you do not leave 6/12 on the page. 19/12 is kept as 19/12 and also written 1 7/12. Negative numerators are allowed; the sign sits on the result, not as a “minus mixed number” style from every textbook.

This is not a one-box converter. A single 3/8 → 0.375 belongs on Fraction to Decimal. Ratios (3:8) belong on the ratio page. LCD listing for more than two fractions is not this tool — LCM of the bottoms can help you do that by hand.

Formula

a/b + c/d = (ad + bc) / bd
a/b − c/d = (ad − bc) / bd
a/b × c/d = ac / bd
a/b ÷ c/d = ad / bc

Worked examples

  • Add 1/2 and 1/3

    1/2 + 1/3 → 5/6

  • Divide 1/2 by 1/4

    1/2 ÷ 1/4 → 2

Useful notes

  • Inputs are integers. Convert mixed numbers to improper fractions first.
  • Zero denominators and division by zero are rejected.
  • The decimal is a rounded display of the same rational.

FAQ

How do I add fractions with different denominators?

Cross-multiply onto a common denominator: 1/2 + 1/3 = (3 + 2) / 6 = 5/6.

How do I simplify the answer?

Divide the numerator and denominator by their greatest common factor. 6/12 and 1/2 are the same number; this tool keeps 1/2.

Can I enter a mixed number?

Not directly. Convert it first: 1 1/2 is 3/2. The result side will still show a mixed number when the answer is improper.

What is 3/4 − 1/6?

Common denominator 12: 9/12 − 2/12 = 7/12.

Why is 2/3 × 3/4 not left as 6/12?

6 and 12 share a factor of 6. The tool always reduces. 6/12 and 1/2 are the same number.

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