Watermelon is very low in calories. Here are the typical calorie counts based on serving size:

• About 30 calories per 100 grams of watermelon without skin

• One cup (approximately 152 grams) of diced watermelon contains around 46 calories

• One slice or wedge (1/16 of a whole melon) has about 86 calories

• A whole watermelon can contain roughly 1360 calories, depending on its size

In summary, watermelon is a low-calorie fruit, mostly made up of water, making it a refreshing and hydrating snack with minimal calorie intake.