Calories in Onion
Onion has about 44 calories per 1 medium onion (110 g), or 40 kcal per 100 g. That serving gives you 1.2 g protein, 10.3 g carbs and 0.1 g fat.
Nutrition facts
Lab-analysed values from USDA FoodData Central (Onions, raw).
| Nutrient | Per 100 g | 1 medium onion (110 g) | 100 g (100 g) |
|---|---|---|---|
| Calories | 40 kcal | 44 kcal | 40 kcal |
| Protein | 1.1 g | 1.2 g | 1.1 g |
| Carbohydrates | 9.3 g | 10.3 g | 9.3 g |
| Fat | 0.1 g | 0.1 g | 0.1 g |
| Fiber | 1.7 g | 1.9 g | 1.7 g |
| Sugar | 4.2 g | 4.7 g | 4.2 g |
| Sodium | 4 mg | 4 mg | 4 mg |
About Onion
A raw onion is about 40 kcal per 100 g. On its own it barely registers; fried in oil for a masala base it absorbs a lot of fat, and crispy fried onion (birista) is over 400 kcal per 100 g.
Tip: Raw onion with lemon alongside a meal is practically zero; fried onion garnish is the opposite.
Burn off 44 kcal
Rough estimates for a 70 kg adult.
- Brisk walking10 min
- Running4 min
- Cycling6 min
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Common questions
How many calories are in onion?+
About 44 kcal per 1 medium onion (110 g), or 40 kcal per 100 g. Low-calorie raw; absorbs a lot of oil when fried.
How many calories in 100 g of onion?+
100 g (100 g) is roughly 40 kcal with 1.1 g protein, 9.3 g carbs and 0.1 g fat.
How much protein is in onion?+
About 1.2 g per 1 medium onion. It is not a major protein source, so pair it with daal, yogurt, eggs, chicken or fish to balance the meal.
Is onion good for weight loss?+
Onion is low in calorie density (40 kcal per 100 g), so it fills you up for relatively few calories and fits easily into a weight-loss diet.
Related foods
Values are averages for general information only and are not medical or dietary advice. Actual calories depend on the recipe, cooking oil and portion size. Browse all foods in our food calorie database.