Onion calories & macros
40 calories per 100 g · 44 calories per 1 medium (110 g). Onion (raw).
Raw onion is 40 calories per 100 g, so a whole medium one adds about 44 to a dish — negligible in the context of a meal. What matters for tracking is what happens next: caramelising an onion drives off water and usually adds oil, so the same onion can arrive on the plate carrying 150 calories or more. Log the fat, not the onion.
Full nutrition facts
| Nutrient | Per 100 g | Per 1 medium (110 g) |
|---|---|---|
| Calories | 40 | 44 |
| Protein | 1.1 g | 1.2 g |
| Carbohydrate | 9.3 g | 10.2 g |
| Fat | 0.1 g | 0.1 g |
| Fiber | 1.7 g | 1.9 g |
| Sugar | 4.2 g | 4.6 g |
Source: USDA FoodData Central (Onions, raw). Values are for the edible portion and vary with variety, ripeness, and preparation.
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Point your phone at the plate and Cibo logs onion and everything around it in seconds — calories, protein, carbs, and fat, no weighing or searching required.
Put onion in context
- Work out your daily budget with the TDEE calculator or plan a cut with the calorie-deficit calculator.
- Logging feels like a chore? How to count calories without weighing food.
- Paying for barcode scanning elsewhere? Apps that still scan for free — or see how Cibo compares to Cronometer and MacroFactor.
Frequently asked
How many calories in a medium onion?
About 44 calories raw (110 g). Fried or caramelised, the count depends almost entirely on how much oil or butter went into the pan.
Are onions high in carbs?
Moderately, for a vegetable: 9.3 g per 100 g, of which 1.7 g is fiber. In the quantities normally used for flavour, that is a rounding error; in a dish built on onions, it is worth counting.