Vegetables
How many calories are in an onion?
Onion has 40 calories per 100 g. A typical serving (1 medium (2-1/2" dia), 110 g) has 44 calories.
- Calories, 1 medium (2-1/2" dia) (110 g)
- 44
- Calories per gram
- 0.4
Very low energy density
Calories in onion by portion
| Portion | Calories | Protein | Carbs | Fat |
|---|---|---|---|---|
| 1 cup, chopped (160 g) | 64 | 1.8 g | 14.9 g | 0.2 g |
| 1 slice, medium (1/8" thick) (14 g) | 6 | 0.2 g | 1.3 g | 0 g |
| 1 medium (2-1/2" dia) (110 g) | 44 | 1.2 g | 10.2 g | 0.1 g |
| 1 large (150 g) | 60 | 1.7 g | 14 g | 0.2 g |
| 10 rings (60 g) | 24 | 0.7 g | 5.6 g | 0.1 g |
| 1 tbsp chopped (10 g) | 4 | 0.1 g | 0.9 g | 0 g |
| 1 cup, sliced (115 g) | 46 | 1.3 g | 10.7 g | 0.1 g |
| 1 slice, thin (9 g) | 4 | 0.1 g | 0.8 g | 0 g |
| 100 g | 40 | 1.1 g | 9.3 g | 0.1 g |
Weigh it instead? Enter your own grams in the food lookup.
Where the calories come from
- Protein 10%
- Carbs 88%
- Fat 2%
Nutrition per 100 g
- Calories
- 40
- Protein
- 1.1 g
- Carbs
- 9.3 g
- Fat
- 0.1 g
- Fibre
- 1.7 g
- Sugar
- 4.2 g
- Sodium
- 4 mg
Vegetables: lightest first
FAQ
Is an onion high in calories?
It has 0.4 calories per gram, which counts as very low energy density. That's more calories per gram than 10% of the 106 foods we track.
How many calories are in 100 g of onion?
40 calories, with 1.1 g protein, 9.3 g carbs and 0.1 g fat.
Where do the calories in an onion come from?
Roughly 10% from protein, 88% from carbs, 2% from fat.
Where do these numbers come from?
USDA FoodData Central, entry 170000: "Onions, raw" (SR Legacy). Brands and recipes vary, so a package label can differ a little.
Source
General information, not medical advice. Values are averages; brands and recipes vary.