Here is the calorie content for the average type of green apple:
15 calories in 1 oz or 28g of green apple with peel
14 calories in 1 oz or 28g of green apple without peel
53-55 calories in 1 small green apple, about 2.5 diameter, with peel
77-81 calories in 1 medium green apple, 2.75 diameter, with peel
110-118 calories in 1 large green apple, 3.25 diameter, 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.