Question of the Day: Are banana peppers hot or mild?
Quick Answer: Most banana peppers are very mild, with a Scoville Heat Index rating of only 0-500SHU. This puts them in the same range as bell peppers.
There have been some spicier hybrids developed, but these generally will be marketed under different names. Hot Hungarian peppers are occasionally mistaken for banana peppers since they look similar and can be referred to as yellow wax peppers.