The spiciness of peppers is call pepper pungency. Pepper pungency is based on the Scoville Heat Scale whereas the mildest pepper, bell peppers, have 0 Scoville Heat Units (SHU) and the current Guinness Book of World Records record holder for the spiciest pepper is the Carolina Reaper has a max SHU of 2,200,000. We consider mild peppers as having less than 25,000 SHU. These peppers are generally tolerated well by most people. They are slightly spicy but can add dynamic flavors to a variety of recipes.