The number of calories in an avocado varies by size, but here are typical values:

• A whole medium avocado contains approximately 225 to 250 calories

• Half a medium avocado has about 130 to 160 calories

• Per 100 grams, avocado provides roughly 160 calories

The calories primarily come from fat, mostly healthy monounsaturated fats, with around 20-25 grams of fat per whole avocado, of which about 15 grams are monounsaturated fat

. Avocados also contain fiber, carbohydrates, and protein but in smaller amounts. In summary, a medium avocado has about 225-250 calories, with half of it around 130-160 calories, making it a calorie-dense but nutrient-rich fruit.