How many carbs are in popcorn?
One ounce of popped popcorn (about 3.5 cups) has about 22g of carbohydrate and 18g of net carbs. Air-popped popcorn is one of the higher-fiber whole grain snacks.
Carbs by portion
| Portion | Total carbs | Fiber | Net carbs |
|---|---|---|---|
| 1 oz popped (28g) | 21.8g | 4.1g | 17.7g |
| 1 cup (8g) | 6.2g | 1.2g | 5.1g |
| 1 oz (28g) | 22.1g | 4.1g | 17.9g |
| 100 grams | 77.8g | 14.5g | 63.3g |
Net carbs
One ounce of popped popcorn has about 18g of net carbs, which is total carbs (22g) minus about 4g of fiber. Popcorn is a whole grain and its fiber content is notably higher than crackers or pretzels of the same weight. See the net carbs guide.
Glycemic index of popcorn
The glycemic index of popcorn is about 65. Air-popped popcorn has a moderate GI. Despite being a whole grain, the popping process gelatinizes the starch and increases digestibility compared to the raw kernel. Microwave buttered popcorn has a similar GI because the fat does not dramatically change starch digestion speed.
For diabetes
One ounce of popcorn is about 22g of carbs with a moderate GI of 65. The volume is high (about 3.5 cups per ounce), which makes it one of the more portion-satisfying snacks for its carb count. Movie theater popcorn, however, is often sold in 6 to 15 cup buckets (170 to 425g), delivering 100 to 300g of carbs plus added butter. Count the full portion, not just the serving size on the bag. See the diabetes carb-counting guide.
Keto and low carb
One ounce of popcorn has about 18g of net carbs. It does not fit strict keto. A two-cup serving (about 16g) is borderline, but most keto plans avoid popcorn because it is difficult to stop at two cups.
Good to know
Air-popped, plain popcorn is the most carb-efficient form. Microwave popcorn adds fat (butter) and often salt and flavoring, but the carb count is similar. Kettle corn adds sugar, typically adding 3 to 4g of carbs per ounce over plain. Cheese popcorn and caramel corn are substantially higher in carbs. The 94% fat-free microwave bags still have nearly the same carbs as regular because the fat was minimal to begin with.
Full nutrition (per 100g)
- Calories: 387.0 kcal
- Carbohydrate: 77.78g
- Fiber: 14.5g
- Sugars: 0.87g
- Protein: 12.94g
- Fat: 4.54g
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Get the appFrequently asked questions
How many carbs are in popcorn?
One ounce of popped popcorn (about 3.5 cups) has about 22g of carbohydrate. One cup of plain popcorn has about 6g of carbs.
How many net carbs are in popcorn?
One ounce has about 18g of net carbs, which is total carbs (22g) minus about 4g of fiber.
Is popcorn keto?
Mostly not. One ounce has about 18g of net carbs. A small 2-cup portion (about 9g of net carbs) may fit for some people, but it's hard to stop at two cups.
Is popcorn a good snack for diabetics?
In a measured portion, popcorn is a better snack than pretzels or crackers because of its higher fiber content and larger volume per ounce. Count the full serving, not just one cup.
Does butter on popcorn change the carbs?
No. Butter adds fat and calories but zero carbs. Plain buttered popcorn has the same carb count as plain air-popped.