Fraction Guide and Calculator
Adding Fractions With Unlike Denominators
Add fractions with different denominators step by step. Find a common denominator first, convert each fraction, add the numerators, and reduce the result.
Adding fractions example
Example: 1/4 + 1/6 uses LCD 12. Convert to 3/12 + 2/12, then add to get 5/12. Never add the denominators.
How this page connects to fraction work
Use the LCD calculator first when the denominators are difficult or when more than two fractions are involved. Link to the LCD calculator when you need to test additional denominators.
Frequently Asked Questions
Why do fractions need a common denominator?
Fractions must use the same denominator before their numerators can be added or subtracted directly.
Can I use the LCD calculator for more than two fractions?
Yes. Enter the denominators or fractions and the calculator finds the least shared denominator.