Onion: weights & conversions
A US cup of onion weighs about 160 g. One weighs about 110 g. 100 g is 40 calories and 1.1 g of protein.
Also written as: onions, yellow onion, white onion, sweet onion, vidalia onion.
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1 cup of onion is about 160 grams.
Cups to grams
What each measure of onion weighs, from the cup weight above.
| Volume | Grams | Ounces |
|---|---|---|
| 1 cup | 160 g | 5.64 oz |
| 3/4 cup | 120 g | |
| 2/3 cup | 107 g | |
| 1/2 cup | 80 g | |
| 1/3 cup | 53.3 g | |
| 1/4 cup | 40 g | |
| 1 tablespoon | 10 g | |
| 1 teaspoon | 3.33 g |
Weight per piece
What a recipe means when it counts onion instead of weighing it.
| Count | Grams | Ounces |
|---|---|---|
| 1 onion | 110 g | 3.88 oz |
| 2 onions | 220 g | |
| 3 onions | 330 g | |
| 4 onions | 440 g | |
| 6 onions | 660 g | |
| 12 onions | 1320 g |
Ounces and pounds
The weights an older recipe card is most likely to use.
| Weight | Grams | Ounces |
|---|---|---|
| 1 oz | 28.3 g | |
| 4 oz (1/4 lb) | 113 g | |
| 8 oz (1/2 lb) | 227 g | |
| 1 lb | 454 g | |
| 100 g | 100 g |
Nutrition
Per 100 g of edible portion, transcribed from USDA reference data, and scaled to the measures above.
| Measure | Calories | Protein | Fat | Carbs | Fiber | Sodium |
|---|---|---|---|---|---|---|
| Per 100 g (100 g) | 40 | 1.1 g | 0.1 g | 9.3 g | 1.7 g | 4 mg |
| Per cup (160 g) | 64 | 1.76 g | 0.16 g | 14.9 g | 2.72 g | 6 mg |
| Per tablespoon (10 g) | 4 | 0.11 g | 0.01 g | 0.93 g | 0.17 g | 0 mg |
| Per onion (110 g) | 44 | 1.21 g | 0.11 g | 10.2 g | 1.87 g | 4 mg |
| Per 4 oz (113 g) | 45 | 1.25 g | 0.11 g | 10.5 g | 1.93 g | 5 mg |
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Common questions
- How many grams are in a cup of onion?
- One US cup of onion weighs about 160 g (5.64 oz). A tablespoon is about 10 g and a teaspoon about 3.33 g.
- How many cups is 100 g of onion?
- 100 g of onion is about 0.63 cups — near enough to 5/8 of a cup in a measuring cup.
- How much does one onion weigh?
- One onion weighs about 110 g (3.88 oz), so a pound is roughly 4 of them.
- How many calories are in onion?
- Onion has about 40 calories per 100 g, which works out to roughly 64 calories a cup.