Onion - food photo
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Calories in Onion

USDA Verified · FDC 170000 · Jan 2026
44 calories
per 1 medium onion (110g)
1.1g
Protein
9.3g
Carbs
0.1g
Fat
1.7g
Fiber

Per 100g raw

Serving Sizes & Calories

Serving SizeWeightCalories
1/2 cup chopped80g32 cal
1 cup chopped160g64 cal
1 medium onionStandard110g44 cal
1 large onion150g60 cal
1 slice (1/4" thick)14g6 cal
100g100g40 cal

40 calories per 100g raw

Complete Nutrition Facts

Per 100g raw
40 calories
Protein1.1g
Carbohydrates9.3g
Sugar4.2g
Fat0.1g
Fiber1.7g
Sodium4mg
Potassium146mg

How Onion Compares

Onion next to similar foods, all values per 100g:

FoodCaloriesProteinCarbsFatFiber
Onion401.1g9.3g0.1g1.7g
Garlic1496.4g33.1g0.5g2.1g
Potato772g17.2g0.1g2.1g
Tomato180.9g3.9g0.2g1.2g
Bell Pepper230.7g4.8g0.1g0.9g

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Related Foods

Often Paired With

BurgersSteakPeppersMushrooms

Diet Compatibility

Onion fits these diet categories:

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Burn These Calories

Calculate how long it takes to burn 44 calories from onion:

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