How Many Calories Do A Big Banana Have?

A big banana (8 inches) would have about 121 calories (USDA). Depending on their size, smaller bananas can have from 86 to 108 calories in them.

Most of the calories in bananas come from carbohydrates. If the fruit is very ripe, it will have a high quantity of sugars and a little less ripe bananas would have more starch in them. Only about 1% of the calories come from proteins.

The complete nutritional information for a large banana (8 inches) is:

Approximate weight of banana - 136g
Total Calories - 121
Calories from fat - 4
Total Carbohydrate - 31.06g
  Sugars - 16.63g
Protein - 1.48g
Sodium - 1mg
Potassium - 487mg

Also found in bananas are:
Vitamin A
Vitamin C
Iron
Calcium

If talking about calories a big size banana contains approx 100 to 150 calories!