LCD, LCM, and GCF are related but serve different purposes. LCM finds the smallest shared positive multiple of integers. LCD is that same LCM applied specifically to fraction denominators. GCF, also called GCD, finds the largest shared factor. Use the main calculator for fractions or the LCM of denominators tool for integer-only input.
A short example
For denominators 4 and 6, GCF(4,6) = 2 and LCM(4,6) = 12. Therefore the LCD of 3/4 and 5/6 is 12.
Explore the exact product relationship in the LCD using GCF calculator.