What can burning 300 calories do for you. 300 calories is the amount of calories in about 1 cup of ice cream. In a slice of large pizza there is about 300 calories in it. If you like candy, a whole candy bar has about 300 calories in it and a bag of gummy bears has about 300 calories too. Enjoy these foods and many more without worrying by burning 300 calories, Download now and find out how to!