A whole watermelon, measuring about 15 inches long by 7.5 inches in diameter, contains approximately 1,360 calories according to the United States Department of Agriculture (USDA) data. In smaller servings:
- 1 cup of diced watermelon has about 46 calories.
- 1 slice (about 1/16 of a whole watermelon) contains around 86 calories.
- Watermelon contains about 30 calories per 100 grams.
These calories mainly come from carbohydrates, primarily natural sugars like sucrose, fructose, and glucose, with very little fat or protein. Watermelon is over 90% water, making it a low-calorie and hydrating fruit.
