How Many Calories in Onion?
A onion contains 40 calories per 100g. A typical 1 medium onion (110g) provides about 44 calories. Onion is low in calories.
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Onion Nutrition Facts
| Nutrient | Per 100g | Per serving (110g) |
|---|---|---|
| Calories | 40 kcal | 44 kcal |
| Protein | 1.1g | 1.2g |
| Carbohydrates | 9.3g | 10.2g |
| of which Sugars | 4.2g | 4.6g |
| Fat | 0.1g | 0.1g |
| of which Saturates | 0.0g | 0.0g |
| Fibre | 1.7g | 1.9g |
| Sodium | 4.0mg | 4mg |
| Potassium | 146.0mg | 161mg |
| Calcium | 23.0mg | 25mg |
| Iron | 0.2mg | 0.2mg |
| Vitamin C | 7.4mg | 8.1mg |
| Vitamin A | 0.0µg | 0µg |
Frequently Asked Questions
How many calories in onion per 100g?
Onion contains 40 calories per 100g, based on USDA reference data.
Is onion high in calories?
A 1 medium onion of onion (110g) has around 44 calories — roughly 2% of a 2,000-calorie daily intake.
Is onion good for weight loss?
At 40 calories per 100g, onion is relatively low in calories and can fit well into a weight-loss diet. A 1 medium onion provides about 44 calories.
How much protein is in onion?
Onion contains 1.1g of protein per 100g.
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Nutrition data sourced from the USDA FoodData Central database (public domain, CC0 1.0). Values are per 100g unless stated. Figures may vary slightly depending on preparation method and ripeness.