When to use this calculator
Add, subtract, multiply or divide two fractions and simplify the answer. Denominators must be positive. Division by a zero-valued second fraction is undefined.
Explore the fractions & mixed numbers calculators for other questions in this topic. For a related calculation, use the Improper Fraction to Mixed Number Calculator: Express a non-negative improper fraction as a whole part and remainder.
Keep the operation and denominator rules separate
To add 1/2 and 1/3, use a common denominator: 3/6 + 2/6 = 5/6. Multiplication uses 1 × 1 over 2 × 3 instead, giving 1/6. Division reverses the second fraction before multiplying; the second fraction must not have a zero value.
PUTTING IT INTO PRACTICE
Fraction: a worked example
The values below are an illustrative example, not a recommendation. Replace them with measurements or assumptions that match your question.
| Input | Example value |
|---|---|
| First numerator (integer) | 1 |
| First denominator (integer) | 2 |
| Operation | add |
| Second numerator (integer) | 1 |
| Second denominator (integer) | 3 |
| Result | 5/6 |
- Check the input labels and enter the example values above.
- Apply the relationship: Use a common denominator for addition/subtraction; multiply or invert for products/quotients..
- The result is 5/6 , rounded for display.
How to interpret your result
Denominators must be positive. Division by a zero-valued second fraction is undefined.
Use positive nonzero denominators and whole-number numerator inputs. A mixed number combines a whole part and a fractional remainder. Decimal conversion here covers finite decimals, not a claim about an unmarked repeating pattern.
Frequently asked questions
How do I enter a negative fraction?
Put the minus sign in the numerator and keep the denominator positive. The output carries a single sign and is reduced to lowest terms.
Why simplify a fraction?
Simplification divides both parts by their greatest common divisor while preserving the value. It makes equivalent fractions easier to compare.
When is the fraction calculator useful?
Add, subtract, multiply or divide two fractions and simplify the answer. Denominators must be positive. Division by a zero-valued second fraction is undefined.
How do I use the fraction calculator?
Enter first numerator (integer), first denominator (integer), operation, second numerator (integer), second denominator (integer). The result updates automatically. Use the units shown beside each input; the example values illustrate the method.
Which formula does this calculator use?
Use a common denominator for addition/subtraction; multiply or invert for products/quotients..
What should I check before using the result?
Denominators must be positive. Division by a zero-valued second fraction is undefined.
How are results rounded?
Scalar numbers display up to six decimal places, with scientific notation for very large or small values. Text, fraction, date and schedule outputs use the format described on the tool. Intermediate calculations use JavaScript floating-point arithmetic. Keep sensible precision for your measurements.
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