Calories in a banana: medium, large and per 100 g

A medium banana (120 g peeled) has about 105 calories, and 100 g of banana has 89 kcal. A smaller one of 80 g is about 70 kcal and a large one of 150 g about 135. As a snack that holds until lunch, it's one of the easiest things in the day to count.

Bananas have an unfair reputation on diets, probably because they're sweet. When I started weighing mine, a banana turned out to have fewer calories than a piece of pogača, the round bread we eat at home, or a handful of peanuts. The numbers below are from USDA FoodData Central, the US Department of Agriculture's nutrient database.

How many calories are in a banana per 100 g?

A banana has 89 kcal per 100 g of peeled fruit, with about 1.1 g protein, 0.3 g fat and 20 g carbohydrate, plus 2.6 g fibre. There is almost no fat.

What matters is that this is the weight of the peeled banana. If you weigh it with the peel, you count the peel too, and the number comes out too high. Peel first, then weigh.

How many calories are in a medium or large banana?

A medium banana (about 120 g peeled) has about 105 kcal and a large one (150 g) about 135 kcal.

Banana, peeled	Weight	kcal
a smaller one	80 g	70
per 100 g	100 g	89
medium (Dietary Guidelines)	1 banana	105
medium, my table	120 g	105
large, my table	150 g	135

Source: USDA FoodData Central 173944 (89 kcal per 100 g, the value in my food table); the medium banana from the Dietary Guidelines' food tables. Other weights are 89 × grams ÷ 100, rounded.

The Dietary Guidelines for Americans list a medium banana at 105 kcal next to 89 kcal per 100 g, which puts it at about 118 g; my table uses 120 g, and both round to 105. If you don't have a scale, log a medium banana and mark it as an estimate.

Does a ripe banana have more calories than a green one?

A ripe banana has about the same calories as a green one. As a banana ripens, its starch turns into sugar, so a ripe one is sweeter and softer, but its energy barely changes. My table has no separate values for green and ripe bananas, so I won't invent a difference. Pick the one you like: a ripe banana you finish is a better snack than a green one you leave half-eaten.

Is a banana better than an apple for weight loss?

An apple has fewer calories than a banana: 52 kcal per 100 g against 89. A medium apple of 165 g is about 85 kcal, a medium banana about 105. That's a 20-calorie difference, smaller than a teaspoon of butter.

So the choice comes down to what keeps you full and what you'll actually eat. I take a banana when I need something I can eat at my desk without a knife.

Do bananas make you gain weight?

Bananas don't make you gain weight any more than other foods with the same calories. Weight follows what you eat over days and weeks, and a 105-calorie banana fits into almost any plan. What surprises people is what goes with it:

• a banana and a 30 g handful of peanuts: about 285 kcal
• a banana with 200 g of drinkable yogurt: about 225 kcal
• a smoothie with a banana, 200 ml of milk and a spoonful (20 g) of honey: about 280 kcal

If you have diabetes or kidney disease, ask your doctor or dietitian how fruit fits into your day; this post isn't medical advice.

How many bananas a day is OK?

For most people, one or two bananas a day fit easily, about 105 to 215 kcal. If the banana replaces biscuits or a chocolate bar, it is almost always the better trade in calories and in how long it keeps you going.

A medium banana also has 422 mg of potassium, according to the same Dietary Guidelines table, which ranks bananas among the common sources of it.

Should I eat a banana before or after a workout?

A banana works before or after a workout: a medium one has about 24 g of carbohydrate, and it's easy to carry and eat without making a mess. After training I have it with something that has protein, like a glass of yogurt.

What about banana bread, chips and smoothies?

A banana in a smoothie counts by its weight before blending, and the milk, yogurt and anything else are separate items. A bottled smoothie has a label, and that is more accurate than any estimate.

In banana bread or cake, the banana is usually the smaller part of the count. Flour, sugar and fat carry most of the calories, so "with banana" doesn't make a slice light.

Dried bananas and banana chips are a different food. With the water gone, the same grams carry much more energy, and chips are often fried and sweetened as well. My table has no row for them, so for a bought pack, go by the label.

How do I log a banana quickly?

To log a banana, peel it, weigh it and multiply the grams by 0.89. Without a scale, log a medium banana (105 kcal) and mark it as an estimate. If you share one, log your half. In Calorko, the Android app I'm building, you can also just photograph it and correct the size with a slider.

In short

• A banana has 89 kcal per 100 g, peeled.
• Medium about 105 kcal, large (150 g) about 135.
• Ripe and green bananas have about the same calories.
• A banana doesn't make you gain weight; watch what you eat with it.