Fraction Guide and Calculator
LCD vs LCM: What Is the Difference?
Learn how LCD and LCM relate. The LCM is a multiple shared by integers; the LCD is the LCM of fraction denominators.
LCD versus LCM example
For denominators 4 and 6, the LCM is 12. When those integers are denominators, 12 is also the LCD for fractions with those denominators.
How this page connects to fraction work
Use LCM for integer multiples and LCD when rewriting fractions over a shared denominator. 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.