How many calories in green grapes? Green grapes can be seeded or seedless. A single seeded grape contains 4 calories and a seedless grape contains 3 calories. A single grape has 2% vitamin A, 29% vitamin C, 2% calcium, 2% iron, 3% protein, 10% carbohydrates and 6% dietary fiber. It’s rich in vitamin C. A cup of grapes may vary in calories between 90 – 110 calories. As a fruit with low calorie it is preferred as a favorite diet and a common snack item.