Add two fractions, simplify the result, and see the decimal equivalent.
Last updated: June 2026 | By Patchworkr Team
Fraction addition combines parts of a whole. The pieces need to be measured in the same-sized parts before you can add them together.
That is why fractions with different denominators must be rewritten with a shared denominator first.
In a fraction, the numerator tells you how many parts you have and the denominator tells you how many equal parts make a whole.
When fractions already have the same denominator, add the numerators and keep the denominator the same.
This is the easiest kind of fraction addition because you do not need to rewrite either fraction.
When denominators differ, first rewrite the fractions using a common denominator.
Once the denominators match, add the numerators and simplify if needed.
The least common denominator, or LCD, is the smallest denominator both fractions can share.
Using the LCD keeps the arithmetic simpler and often reduces the amount of simplification needed afterward.
For example, the LCD of 1/2 and 1/3 is 6, which makes the addition straightforward.
If you usually work with mixed numbers, you may see inputs like 1 1/2 + 2 1/3. This calculator uses fractions, so mixed numbers need to be converted first if you want to enter them manually.
If the result is improper, that is still a valid answer. You can leave it as a fraction or convert it to a mixed number afterward.
Can I use negative fractions?
Yes. The calculator supports negative numerators and denominators.
Why do denominators need to be non-zero?
Because division by zero is undefined in mathematics.
Does it simplify automatically?
Yes. The result is reduced to lowest terms.
Does it show decimals too?
Yes. It displays a decimal approximation alongside the simplified fraction.
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