No. A medium banana contains ~25g net carbs, exceeding most keto daily limits of 20–50g.

Contents

Calories Calculator Nutrition Facts Vitamins Calories by Weight Macros Micronutrients Health Benefits Diet Guide FAQ Related Foods

Calories in a Banana

Q: How many calories in a banana?

A medium banana (118g) contains 105 calories. Per 100g, bananas have 89 calories. A small banana (81g) has 72 kcal and a large (136g) has 121 kcal.

Q: Is banana good for weight loss?

Yes, in moderation. At 105 kcal per medium banana with 3.1g fiber, bananas are filling and replace higher-calorie processed snacks well.

Q: Is banana high in sugar?

A medium banana contains 14.4g of natural sugar. The fiber slows absorption, giving a medium glycemic index of ~51.

Updated July 2026 · Reviewed by CaloriesCalc Team · Source: USDA FoodData Central

kcal

per 100g

22.8

Carbs

1.1

Protein

0.3

Fat

2.6

Fiber

kcal small (81g)

105

kcal medium (118g)

121

kcal large (136g)

✔ Naturally sweet ✔ High in potassium ✔ Great pre-workout ✔ Fat free ✔ Gluten free ✔ Vegan

Banana nutrition facts and calories per 100g

🍌 Calculate Calories for Any Banana Weight

Weight 100g

Nutrition Facts

Per 100g (raw banana)

* % Daily Value based on a 2,000 kcal diet.

Quick summary: Bananas contain 89 calories per 100g and 105 calories per medium banana. Rich in potassium (358mg), vitamin B6 (22% DV), and natural sugars with 2.6g of fiber, bananas provide quick, sustained energy ideal for exercise. With only 0.3g of fat and being naturally fat-free, gluten-free, and vegan, they fit most dietary patterns except strict keto.

Vitamins & Minerals — per 100g

Nutrient	Amount	% Daily Value
Potassium	358 mg	8%
Vitamin B6	0.37 mg	22%
Vitamin C	8.7 mg	10%
Magnesium	27 mg	6%
Manganese	0.27 mg	12%
Copper	0.08 mg	9%
Folate (B9)	20 µg	5%
Riboflavin (B2)	0.07 mg	5%
Niacin (B3)	0.67 mg	4%
Phosphorus	22 mg	2%

Calories in Banana by Weight

Weight	Calories	Carbs	Protein	Fat

Calories in Different Banana Sizes

Size	Weight	Calories	Carbs	Protein	Fat
Extra small	81g	72 kcal	19g	0.9g	0.2g
Small (6")	101g	90 kcal	23g	1.1g	0.3g
⭐ Medium (7")	118g	105 kcal	27g	1.3g	0.4g
Large (8")	136g	121 kcal	31g	1.5g	0.4g
Extra large (9"+)	152g	135 kcal	35g	1.7g	0.5g
1 cup sliced	150g	134 kcal	34g	1.6g	0.5g
1 cup mashed	225g	200 kcal	51g	2.5g	0.7g

Macronutrient Breakdown — per 100g

Carbohydrates22.8g · 91% of calories

Protein1.1g · 5% of calories

Fat0.3g · 3% of calories

Fiber2.6g (included in carbs)

Bananas are almost exclusively a carbohydrate food. The majority of carbs come from sugars in ripe bananas; unripe bananas contain more resistant starch.

Micronutrient Highlights

⚡

Potassium

358 mg

8% Daily Value

Regulates blood pressure & muscle function

🧠

Vitamin B6

0.37 mg

22% Daily Value

Supports nervous system & serotonin production

🛡

Vitamin C

8.7 mg

10% Daily Value

Supports immune system & skin health

🌿

Fiber

2.6 g

9% Daily Value

Supports digestion & gut bacteria

💪

Magnesium

27 mg

6% Daily Value

Relaxes muscles & supports energy production

🔬

Manganese

0.27 mg

12% Daily Value

Activates antioxidant enzymes

Banana Health Benefits & Nutrition

Is Banana Good for Weight Loss?

At 89 kcal per 100g, bananas are a moderate-calorie fruit. A medium banana provides 3.1g of dietary fiber which promotes satiety and slows digestion. Studies consistently associate higher fiber intake with lower body weight over time. One banana at 105 kcal is far more filling than most processed snacks of similar calorie content.

Bananas as Pre-Workout Fuel

A medium banana eaten 20–30 minutes before training provides ~27g of fast-release carbohydrates that peak in the bloodstream right when energy demand is highest. Combined with 422mg of potassium for muscle function, bananas are one of the most practical and cost-effective pre-workout snacks available — used by elite athletes worldwide.

Glycemic Index and Blood Sugar

The glycemic index (GI) of bananas varies with ripeness. Unripe (green) bananas: GI ~30 (low). Ripe yellow bananas: GI ~51 (medium). Overripe bananas: GI 65+ (medium-high). For blood sugar management, slightly underripe bananas are the better choice. Pairing with protein or fat (e.g. peanut butter) further slows the glucose response.

Resistant Starch — Why Greener Bananas Are Better for Gut Health

Unripe bananas contain high amounts of resistant starch — a type of fiber that feeds beneficial gut bacteria and acts as a prebiotic. As bananas ripen, resistant starch converts to simple sugars. If gut health is a priority, partially ripe bananas provide the best combination of resistant starch and palatability.

Banana vs Other Foods — Calorie Comparison

Is Banana Suitable for Your Diet?

✅

Weight loss

In moderation

✅

Vegan

Yes

✅

Paleo

Yes

✅

Gluten-free

Yes

❌

Keto

No — 25g net carbs

⚠️

Diabetic

In moderation

⚠️

Low-FODMAP

Unripe only

✅

High-protein

As carb source

Related Calculators

TDEE Calculator

Daily calorie needs

Calorie Deficit

How much to eat to lose weight

Macro Calculator

Protein, carbs & fat targets

Calories burned at rest

Frequently Asked Questions

How many calories in a banana?

A medium banana (118g) contains 105 calories. Per 100g, bananas have 89 calories. A small banana (81g) has 72 kcal, a large banana (136g) has 121 kcal. Use the slider above to calculate calories for any weight.

Is banana good for weight loss?

Yes, in moderation. At 105 kcal per medium banana, they are filling due to 3.1g of fiber. One banana per day replaces higher-calorie processed snacks well and fits comfortably into most calorie-deficit diets.

Is banana keto?

No. A medium banana contains approximately 25g of net carbs (total carbs minus fiber), which would use up most or all of a typical keto daily carb limit of 20–50g.

Is banana high in sugar?

A medium banana contains 14.4g of natural sugars. These are naturally occurring fructose, glucose, and sucrose — not added sugars. The fiber content slows their absorption, giving a medium glycemic index of ~51.

Can diabetics eat bananas?

In moderation. Unripe bananas have a lower GI (~30). Pairing with protein or fat slows the glucose response. Portion control (half a banana) is practical. Consult your doctor or dietitian for personalised advice.

How many bananas can I eat per day?

One to two medium bananas per day fits well within typical calorie and carbohydrate budgets for active adults. Two medium bananas provide ~54g carbohydrates and 210 calories — account for this in your daily macros.

Are bananas fattening?

No food in isolation causes fat gain — excess calories do. At 89 kcal per 100g, bananas are a moderate-calorie, nutrient-dense food. They become "fattening" only when eaten in large quantities on top of an already sufficient calorie intake.

Sources

Nutrition values sourced from USDA FoodData Central. Values are averages and may vary by variety and ripeness. Not medical advice.