Fraction Calculator
A fraction calculator performs arithmetic on two fractions and reduces the result to lowest terms using the greatest common divisor, rather than leaving an unsimplified or decimal-only answer. Reducing to lowest terms via the greatest common divisor is the same manual process taught in school — dividing both numerator and denominator by their largest shared factor — done automatically here so the result is never left in an unsimplified form like 6/8 instead of 3/4.
How it works
- Enter the numerator and denominator for both fractions.
- Choose add, subtract, multiply, or divide.
- Read the simplified result as a fraction and as a decimal.
Formula Add/subtract via a common denominator; multiply/divide directly; simplify by dividing out the GCD
Frequently asked questions
Is the result always simplified?
Yes — the numerator and denominator are always divided down to lowest terms using their greatest common divisor.
Can I enter negative fractions?
Yes — enter a negative numerator or denominator; the result normalizes to a positive denominator with the sign on the numerator.
What if a denominator is zero?
That is undefined — the calculator will not show a result.
Can I divide by a fraction equal to zero?
No — division by zero is undefined and returns no result.
Does this handle mixed numbers (e.g. 1½)?
Not directly — convert a mixed number to an improper fraction first (1½ = 3/2).