Vegetables
Calories in Onion
Onion has 40 calories per 100g — that’s 44 calories in a typical serving (1 medium · 110 g).
| Nutrient | Per 100g | Per serving1 medium · 110 g |
|---|---|---|
| Calories | 40 kcal | 44 kcal |
| Protein | 1.1 g | 1.2 g |
| Carbs | 9 g | 9.9 g |
| Fat | 0.1 g | 0.1 g |
| Fiber | 1.7 g | 1.9 g |
| Sugar | 4.2 g | 4.6 g |
| Sodium | 4 mg | 4 mg |
Common kitchen measures
| Measure | Weight | Calories |
|---|---|---|
| 1 cup, chopped | ≈ 160 g | 64 kcal |
| 1 tablespoon | ≈ 10 g | 4 kcal |
Gram weights from USDA FoodData Central — reference values, not exact measurements.
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Frequently asked questions
- How many calories are in Onion?
- Onion has 44 calories per 1 medium (110 g).
- How many calories are in 100g of Onion?
- 100g of Onion has 40 calories, 1.1g protein, 9g carbs and 0.1g fat.
- How much protein is in Onion?
- Onion has 1.2g of protein per 1 medium (110 g).
- How many calories are in 1 cup, chopped of Onion?
- 1 cup, chopped of Onion (≈ 160 g) has about 64 kcal.
Values are typical reference figures and vary with brand, preparation, and portion. This is general information, not medical or dietary advice.