How many calories does kickboxing burn?

Depends on how hard you're working, how fit you are, and how much muscles you have to work with. I can burn around of 900 cals in an hour, but it takes some doing to be able to maintain that output for that long. Kickboxing is so intense that most people are unable to do it consistently for one hour. It'll be more like a few minutes workout, then rest, then on it again. This pulls the average down to at a guess 400-600 cals.