Here are the calorie counts. The amounts vary slightly in relation to the type of apple.
53-55 calories in 1 small apple with peel (about 2.5 diameter)
77-81 calories in 1 medium apple with peel (about 2.75 diameter)
110-118 calories in 1 large apple with peel about 3.25 diameter)
52 calories in 3.5 oz or 100g of apple with peel
57 calories in 1 cup of apple and peel
15 calories in 1 oz or 28g of apple with peel
14 calories in 1 oz or 28g of apple without the peel (one calorie less than with peel).
For the free calorie charts showing how many calories you should have in total per day for all foods, and for the Calories in Vegetables Chart, and the Calories in Fruit Chart, see the page links given below. Use the charts as daily guides for weight loss, or weight maintenance once you have reached your target weight.