Red Onion, Raw — USDA FoodData Central nutrition facts (per 100g)

| Nutrient | Amount per 100g |
| --- | --- |
| Ash | 0.43 g |
| Biotin | 0 µg |
| Calcium, Ca | 17 mg |
| Carbohydrate, by difference | 9.93 g |
| Copper, Cu | 0.058 mg |
| Energy | 44 kcal |
| Energy | 186 kJ |
| Fiber, total dietary | 2.2 g |
| Fructose | 1.79 g |
| Glucose | 2.29 g |
| Iodine, I | 0 µg |
| Iron, Fe | 0.24 mg |
| Lactose | 0 g |
| Magnesium, Mg | 11.4 mg |
| Maltose | 0 g |
| Manganese, Mn | 0.119 mg |
| Phosphorus, P | 41 mg |
| Potassium, K | 197 mg |
| Protein | 0.94 g |
| Selenium, Se | 0.5 µg |
| Sodium, Na | 1 mg |
| Sucrose | 1.68 g |
| Sugars, Total | 5.76 g |
| Total dietary fiber (AOAC 2011.25) | 3.97 g |
| Total lipid (fat) | 0.1 g |
| Vitamin C, total ascorbic acid | 8.1 mg |
| Water | 88.6 g |
| Zinc, Zn | 0.17 mg |

Values are raw as published by USDA at the 100g basis — not rounded per 21 CFR 101.9(c) label-declaration rules, and 100g is USDA's publication basis, not a serving size any US nutrition label declares against.

Source: USDA FoodData Central, FDC ID 790577, usda_ff (released 2026-04-30). https://bettermenu.live/tools/ingredient-search/us/foods/red-onion-raw-790577/