man, i cant hold back any longer..i gotta flame you.
dont ask these kinds of questions until doing a little research.there are a bunch of calorie counters out there you can use as reference.
Watermelon???? come on, thats one of the sweetest fruits out there, thus a lot of FRUCTOSE, thus, a lot of CALORIES!! also its a simply sugar which will spike your insulin def. causing some fat storage!