TempoLife › Calorie database › Vegetables › Sweet onion
Sweet onion calories and nutrition facts
100 grams of sweet onion contains 32 calories, with 0.8 g of protein, 7.6 g of carbohydrate and 0.1 g of fat. It provides 0.9 g of fiber and 5 g of sugar per 100 g. Most of its calories come from carbohydrate.
Where the calories come from
Protein 9% Carbs 88% Fat 3%
How sweet onion compares
Per 100 g, against the closest vegetables in this database.
| Food | Calories | Protein | Carbs | Fat |
|---|---|---|---|---|
| Sweet onion | 32 kcal | 0.8 g | 7.6 g | 0.1 g |
| Leeks, cooked | 31 kcal | 0.8 g | 7.6 g | 0.2 g |
| Canned beets, drained | 31 kcal | 0.9 g | 7.2 g | 0.1 g |
| Fennel bulb | 31 kcal | 1.2 g | 7.3 g | 0.2 g |
| Bolthouse Farms Daily Greens vegetable juice | 31 kcal | 0.5 g | 8.1 g | 0 g |
Nutrition facts for sweet onion
| Nutrient | Per 100 g |
|---|---|
| Calories | 32 kcal |
| Protein | 0.8 g |
| Carbohydrate | 7.6 g |
| Fat | 0.1 g |
| Fiber | 0.9 g |
| Sugar | 5 g |
| Salt | 0 g |
Print an EU-style nutrition label for sweet onion — per 100 g and per portion.
Vitamins and minerals in sweet onion
Per 100 g, highest share of the Daily Value first. %DV = the adult Daily Value (FDA reference). USDA reference data — not medical advice.
| Nutrient | Per 100 g | %DV |
|---|---|---|
| Vitamin B6 | 0.13 mg | 8% |
| Copper | 0.06 mg | 7% |
| Vitamin C | 4.8 mg | 5% |
| Potassium | 119 mg | 3% |
| Manganese | 0.08 mg | 3% |
| Thiamin (B1) | 0.04 mg | 3% |
| Calcium | 20 mg | 2% |
| Magnesium | 9 mg | 2% |
See the richest foods per nutrient in the nutrient toplists.
Calories in common sweet onion servings
How many calories in a portion of sweet onion — reference serving estimates with the gram weight shown.
| Serving | Calories | Protein | Carbs | Fat |
|---|---|---|---|---|
| 100 g (100 g) | 32 kcal | 1 g | 8 g | 0 g |
| 1 onion (331 g) | 106 kcal | 3 g | 25 g | 0 g |
Log sweet onion in one tap
TempoLife lets you search this food, pick your portion and save it to a private daily diary — or snap a photo of the whole meal and edit the estimate. Free to start.
Frequently asked questions
How many calories are in sweet onion?
Sweet onion has 32 calories per 100 grams.
How much protein is in sweet onion?
Sweet onion contains 0.8 g of protein per 100 g.
How much sugar is in sweet onion?
Sweet onion contains 5 g of sugar per 100 g. Nutrition values are reference figures; brands and preparation change the real amount, so weigh and log what you actually eat.
Is sweet onion low in carbs?
Yes by the numbers: Sweet onion has 7.6 g of carbohydrate per 100 g. People following low-carb or keto approaches often include foods in this range — portion size and your own plan still decide.
Are these sweet onion calories exact?
No. These are per-100-gram reference values from the USDA FoodData Central SR Legacy source family. Portion size, ripeness, cut and cooking method all change the real number, so treat them as an estimate and log your own portion.
Related foods
Source: USDA FoodData Central SR Legacy #170008 (2018-04 release). US Government work — public domain in the United States. Reference values per 100 g edible portion.
