Density of Candy
The math behind Candies in Container calculators is pretty straight forward. We use basic Euclidean (3D) geometry to compute the volume of the containers based on their shapes. Once we know the volume, we are able to make reasonable estimates based on an average number of candies in a known volume. We (Issac and Poppy) bought large bags of the different types of candies and our candy expert (see picture) measured them in kitchen measuring bowls. Then we counted the number of candies and did the math to get the estimated number of candies in a gallon container. Here the results.
The Candies in a Container calculator uses the following densities of candies: 
- Mini Jelly Beans: 3,500 mini Jelly Bean candies in a gallon.
- Jelly Beans: 930 Jelly Beans in a gallon
- Jumbo Jelly Beans: 736 Jumbo sized Jelly Beans in a gallon
- M&Ms: 3991 plain M&Ms in a gallon.
- Peanut M&Ms: 1248 Peanut M&Ms in a gallon
- Gum Balls: 1264 Gum Balls in a gallon.
- Candy Corn: 1524 kernels of candy corn in a gallon
- Candy Pumpkins: 378 pumpkin candies in a gallon
- Skittles: 3600 Skittles in a gallon
- Tootsie Roll Midgees: 296 Tootsie Roll Midgees in a gallon
These are only an estimates, because the candy manufactures may vary the sizes of the candies, but this is a decent estimate of the average size of the different candies and your guess, using these calculators, will be much less of a guess.
