How to use this calculator
Choose arithmetic, mixed numbers, simplification, or decimal conversion. Mixed numbers first become improper fractions. Results include reduced fraction, mixed-number and decimal forms, and working. A negative whole-number part applies to the entire mixed number.
- Enter calculation, first whole-number part, first numerator and review the remaining options.
- Select Calculate or change a value to update the result. Read the result label and units before copying.
- Use Reset to restore the worked starting values.
Formula and method
Arithmetic accepts safe integer numerators and nonzero integer denominators. Mixed fractional parts are nonnegative with positive denominators. Decimal conversion preserves at most 12 entered decimal places, not an inferred repeating decimal. Big-integer mode supports up to 999 digits per integer and shows up to 24 decimal places.
Worked example
1/2 + 1/3 = 5/6.
Questions about fraction calculator
How do I add fractions with different denominators?
Multiply across to form a common denominator: a/b + c/d = (ad + bc)/(bd). For 1/2 + 1/3 this gives 5/6. Choose Mixed-number arithmetic to enter whole-number parts, or Decimal to fraction to convert a finite decimal exactly.
What assumptions should I check?
Arithmetic accepts safe integer numerators and nonzero integer denominators. Mixed fractional parts are nonnegative with positive denominators. Decimal conversion preserves at most 12 entered decimal places, not an inferred repeating decimal. Big-integer mode supports up to 999 digits per integer and shows up to 24 decimal places.
Are my inputs saved?
Calculations run in your browser. We store only tool IDs for favorites and recent tools. A calculation link contains your inputs only when you explicitly choose to copy one.