There is an average of two servings in one bag of microwaveable popcorn. A serving size is an estimated 6 1/2 cups of popped kernels.
There are an average of 13 cups of popcorn per bag, but this can vary slightly and is dependent on the number of kernels that pop.
There are an average of 15 calories in 1 cup of popcorn made using fat-free butter. There is also an estimated 2 grams of fat in one serving of this popcorn type.
The serving sizes for mini bags of microwave popcorn vary, as does the calorie and fat content. Popcorn is an abundant source of fiber.