Onion

Q: How many calories in 0.25 cup of onion?

About 49 calories, with roughly 1.3g of protein. 0.25 cup weighs about 14g. Use the slider above for any other portion.

Fiber, water, and the vitamins nothing else brings.

349

cal per 100 g

Portion explorer

How much are you eating?

Drag the slider or type grams. Everything below updates live.

= 0.5 oz

Calories

Protein

1.3g

Carbs

11.7g

Fat

0.1g

Protein 10% Carbs 89% Fat 1%

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Onion: 349 cal per 100g, mixed macros.

No single number tells the story. Use the slider to fit it to your day.

Reverse calculator

Work backwards from your target.

To hit grams of protein, eat:

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For calories, eat:

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Burn it off

What per 100 g costs.

Minutes for a 155 lb (70 kg) adult to burn 349 cal. Adjust down for lighter, up for heavier.

Walking

100

min · 3.5 mph

Cycling

min · easy pace

Jogging

min · 5 mph

Swimming

min · freestyle

Estimates from the Compendium of Physical Activities. Real burn depends on weight, intensity, and fitness.

Full nutrient panel · per 100 g

What else is in there.

From USDA FoodData Central (SR Legacy). %DV against the FDA 2,000-calorie reference.

Fiber9.2 g33%

Sugar37.41 g—

Saturated fat0.078 g0%

Cholesterol0 mg0%

Sodium21 mg1%

Potassium1622 mg35%

Calcium257 mg20%

Iron1.55 mg9%

Magnesium92 mg22%

Zinc1.89 mg17%

Vitamin C75 mg83%

Vitamin E0.18 mg1%

Vitamin A1 mcg0%

Vitamin D0 mcg0%

Vitamin B61.6 mg94%

Vitamin B120 mcg0%

Folate166 mcg42%

Niacin0.99 mg6%

Caffeine0 mg—

How it stacks

Compared to its neighbors.

per 100 g, as-served. Same portion, honest comparison.

Potato Flour

Almost identical calories.

Cal357 Protein6.9 g Fat0.3 g

Tomato

91 fewer calories per 100g · +5g protein.

Cal258 Protein14.1 g Fat3 g

Lentils

243 fewer calories per 100g.

Cal106 Protein9 g Fat0.6 g

Common questions

The stuff people actually ask.

How many calories in 0.25 cup of onion?

About 49 calories, with roughly 1.3g of protein. 0.25 cup weighs about 14g. Use the slider above for any other portion.

Is onion actually healthy, or is that marketing?

By the numbers on this page: balanced enough that "healthy" is the wrong axis. It is food.

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