Frequently Asked Questions
Everything you need to know about the Fraction Calculator.
How do you add fractions with different denominators?
Find a common denominator (typically the LCM of the two denominators), rewrite both fractions over it, then add the numerators and keep the common denominator.
How do you multiply fractions?
Multiply the numerators together and the denominators together — no common denominator is needed for multiplication.
How do you divide fractions?
Multiply the first fraction by the reciprocal (flipped version) of the second fraction — dividing by a fraction is the same as multiplying by its inverse.
Why is my answer automatically simplified?
The calculator divides the numerator and denominator by their greatest common factor so the fraction is always shown in lowest terms.
Can I use negative numbers?
Yes — enter a negative sign on the numerator or denominator, and the calculator handles the sign correctly in the result.
What happens if I enter a denominator of zero?
Division by zero is undefined, so the calculator shows an error rather than a result if either denominator is zero.
What's a mixed number?
A mixed number combines a whole number and a proper fraction, like 1 1/2 instead of 3/2 — the calculator shows this alongside the simplified fraction.
Can I enter improper fractions?
Yes — a numerator larger than the denominator (like 7/4) works fine and is converted to a mixed number in the results.
Does this work with whole numbers?
Yes — enter a whole number as a fraction over 1, such as 5/1, and it will combine correctly with any other fraction.
Is this calculator free to use?
Yes, completely free with no sign-up, and it runs entirely in your browser.