Calories in Onions, for use on a sandwich

Generic food Meals and Dishes

Onions, for use on a sandwich contains 38 kcal per 100 g. A typical serving of guideline amount on regular sandwich (15 g) provides about 6 kcal.

Roughly 89% of its calories come from carbohydrates, with 9% from protein and 2% from fat (estimated with general energy factors).

The data comes from the USDA Food and Nutrient Database for Dietary Studies (FNDDS), which calculates values from recipes of the ingredients.

38kcal per 100 g
0.86 gprotein
8.5 gcarbohydrates
0.08 gfat
6kcal in guideline amount on regular sandwich (15 g)

Nutrition facts

Nutrition facts for the selected amount
NutrientAmount per 100 g% DV
Calories C 38 kcal
Total fat C 0.08 g 0.1%
Saturated fat C 0.042 g 0.2%
Cholesterol C 0 mg 0%
Sodium C 1 mg 0%
Total carbohydrates C 8.5 g 3%
Dietary fiber C 1.7 g 6%
Total sugars C 5.8 g
Protein C 0.86 g 2%
Vitamin A C 0 µg0%
Vitamin C C 8.2 mg9%
Vitamin D C 0 µg0%
Vitamin E C 0.02 mg0.1%
Vitamin K C 0.4 µg0.3%
Thiamin (B1) C 0.046 mg4%
Riboflavin (B2) C 0.027 mg2%
Niacin (B3) C 0.12 mg0.7%
Vitamin B6 C 0.12 mg7%
Folate (B9) C 19 µg5%
Vitamin B12 C 0 µg0%
Choline C 6.1 mg1%
Calcium C 17 mg1%
Iron C 0.24 mg1%
Magnesium C 9 mg2%
Phosphorus C 33 mg3%
Potassium C 171 mg4%
Zinc C 0.17 mg2%
Copper C 0.041 mg5%
Selenium C 0 µg0%

% DV: percent of the FDA Daily Value for adults (reference amounts). Letters show how each value was obtained: M measured, C calculated, L label, Z assumed zero, I imputed. Vitamins and minerals not listed were not reported by the source.

Nutritional breakdown

Protein: 9%Carbohydrates: 89%Fat: 2%38kcal / 100 g
  • Protein 9%
  • Carbohydrates 89%
  • Fat 2%

Approximate share of calories, using general energy factors (4 kcal/g protein and carbohydrate, 9 kcal/g fat, 7 kcal/g alcohol).

Vitamins and minerals, % Daily Value per 100 g

Vitamin C9%Vitamin B67%Folate (B9)5%Copper5%Thiamin (B1)4%Potassium4%Phosphorus3%Magnesium2%Riboflavin (B2)2%Zinc2%

Nutritional insights

  • Protein per 100 kcal2.3 gprotein density, useful for comparing foods with different calorie levels
  • Water90.3 gwater per 100 g, which largely explains differences between raw, cooked and dried forms

Full nutrient profile

Fats and cholesterol (2)
Monounsaturated fat C0.013 g
Polyunsaturated fat C0.017 g
Individual fatty acids (19)
EPA (omega-3, 20:5 n-3) C0 g
DHA (omega-3, 22:6 n-3) C0 g
Linoleic acid (omega-6, 18:2) C0.013 g
SFA 4:0 C0 g
SFA 6:0 C0 g
SFA 8:0 C0 g
SFA 10:0 C0 g
SFA 12:0 C0 g
SFA 14:0 C0.004 g
SFA 16:0 C0.034 g
SFA 18:0 C0.004 g
MUFA 18:1 C0.013 g
PUFA 18:3 C0.004 g
PUFA 20:4 C0 g
MUFA 16:1 C0 g
PUFA 18:4 C0 g
MUFA 20:1 C0 g
MUFA 22:1 C0 g
PUFA 22:5 n-3 (DPA) C0 g
Carotenoids (6)
Beta-carotene C1 µg
Lycopene C0 µg
Lutein + zeaxanthin C4 µg
Retinol C0 µg
Carotene, alpha C0 µg
Cryptoxanthin, beta C0 µg
Other components (8)
Water C90.3 g
Alcohol C0 g
Caffeine C0 mg
Theobromine C0 mg
Folic acid C0 µg
Folate, food C19 µg
Vitamin E, added C0 mg
Vitamin B-12, added C0 µg

Other forms of Onions

Raw, cooked, dried and processed versions are separate records with their own measured values.

FoodCaloriesProteinCarbsFat
Onion, raw Raw 40 1.1 g 9.3 g 0.1 g
Onions, cooked, boiled, drained, without salt Cooked 44 1.4 g 10.2 g 0.19 g
Onions, dehydrated flakes Dried or dry 349 9 g 83.3 g 0.46 g
Onions, canned, solids and liquids Canned 19 0.85 g 4 g 0.09 g
Onions, yellow, sauteed Cooked 123 0.95 g 7.9 g 10.8 g
Onions, spring or scallions (includes tops and bulb), raw Raw 32 1.8 g 7.3 g 0.19 g
Onions, young green, tops only 27 0.97 g 5.7 g 0.47 g
Onions, welsh, raw Raw 34 1.9 g 6.5 g 0.4 g
Onions, sweet, raw Raw 32 0.8 g 7.6 g 0.08 g
Onions, cooked, boiled, drained, with salt Cooked 42 1.4 g 9.6 g 0.19 g
Onions, frozen, chopped, cooked, boiled, drained, with salt Cooked 26 0.77 g 6 g 0.1 g
Onions, frozen, chopped, unprepared Frozen 29 0.79 g 6.8 g 0.1 g

Per 100 g. Calories in kcal. n/a: not reported by the source.

Foods with a similar nutritional profile

FoodCaloriesProteinCarbsFat
Pepper, for use on a sandwich 27 0.81 g 5.7 g 0.12 g
Restaurant, Chinese, vegetable chow mein, without meat or noodles 43 1.3 g 5.7 g 1.7 g
Chow mein or chop suey, meatless, no noodles 43 1.3 g 5.7 g 1.7 g
Tomatoes, for use on a sandwich 20 0.82 g 4 g 0.31 g
McDONALD'S, Side Salad 20 1 g 4.3 g 0.19 g
Mushrooms, for use on a sandwich 31 2.9 g 4.1 g 0.35 g
Oatmeal, reduced sugar 85 2.4 g 16.6 g 1.3 g
Lettuce, for use on a sandwich 20 0.92 g 3.7 g 0.1 g

Per 100 g. Calories in kcal. n/a: not reported by the source.

Frequently asked questions

How many calories are in onions?

100 g of onions has 38 kcal. Guideline amount on regular sandwich (15 g): about 6 kcal. Guideline amount on large sandwich (30 g): about 11 kcal.

How much protein is in onions?

Onions contains 0.86 g of protein per 100 g (2% of the 50 g Daily Value), or 0.13 g in guideline amount on regular sandwich (15 g). About 9% of its calories come from protein.

How many carbs are in onions?

Onions has 8.5 g of total carbohydrates per 100 g, including 1.7 g of fiber and 5.8 g of sugars.

How much fat is in onions?

Onions contains 0.08 g of fat per 100 g, of which 0.042 g is saturated (0.2% of the Daily Value).

How much sodium is in onions?

100 g contains 1 mg of sodium, 0% of the 2,300 mg Daily Value.

Does onions have the same nutrition not specified and raw?

No. Per 100 g, onions, for use on a sandwich has 38 kcal, while onion, raw has 40 kcal. Processing changes the water content, so always use the record that matches how you weigh the food.

Where does this nutrition data come from?

From USDA FoodData Central: FNDDS (Survey), record dated October 31, 2024. FoodFactly last checked it on November 6, 2026. Each value above shows whether it was measured, calculated or taken from a label.

Source of the nutrition information

  • USDA FoodData Central: FNDDS (Survey), record 2710252. License: CC0 1.0 (U.S. public domain). Source record dated October 31, 2024. Imported November 6, 2026.

Last updated: . Data quality score: 100/100 (how it is calculated).

General nutrition information, not medical advice. Individual needs differ; see our disclaimer.