Grapes and Diabetes: Carbs, Glycemic Index and Portions
A cup of grapes has about 27 g of carbohydrate (26 g net). Glycemic index: low (48 to 54). Yes, in measured portions. Grapes are small and easy to eat by the handful, so count them out.
Grapes are one of those foods where the portion sneaks up. A cup is a decent chunk of carbohydrate, and most people can eat that in a few minutes without noticing.
Counting a small handful, about a dozen grapes, and putting the rest away is the easiest strategy. Frozen grapes last longer and slow you down.
Carbs in grapes by portion
| Portion | Grams | Carbs (g) | Fiber (g) | Net carbs (g) | Protein (g) |
|---|---|---|---|---|---|
| cup | 151 | 27 | 1.4 | 26 | 1.1 |
| NLEA serving | 126 | 23 | 1.1 | 22 | 0.9 |
| 10 grapes | 49 | 8.9 | 0.4 | 8.4 | 0.3 |
| 100 g (for comparing foods) | 100 | 18 | 0.9 | 17 | 0.7 |
Source: USDA FoodData Central, FDC ID 174683 (Grapes). Net carbs here means carbohydrate minus fiber. “Net carbs” is not an FDA-defined term, so total carbs are shown too. Values are estimates for a typical item; brands, ripeness and size vary.
Glycemic index and glycemic load
GI ranks how fast a food raises blood glucose compared with pure glucose (100). Low is 55 or less, medium 56 to 69, high 70 or more. Red, green and seedless grapes were tested in several countries. Glycemic load multiplies the index by the available carbohydrate in a portion (carbs minus fiber), so it reflects how much you actually eat: low is 10 or less, medium 11 to 19, high 20 or more.
Which published values we used (4)
| Entry | Food as listed | GI |
|---|---|---|
| Suppl. Table 1, #1133 | Grapes, Crimson seedless | 50 |
| Suppl. Table 1, #1134 | Grapes, green, Menidee, seedless | 54 |
| Suppl. Table 2, #2956 | Grapes, Golden no-seed, raw | 48 |
| Suppl. Table 2, #2957 | Grapes, NS | 49 |
Atkinson FS et al. International tables of glycemic index and glycemic load values 2021. Am J Clin Nutr 2021;114(5):1625-1632. Glucose reference (glucose = 100); values from studies that used white bread were converted by the authors. Where studies differ we show the range, not an average.
Glycemic index is only one piece of the picture. The same food can give a different response depending on ripeness, cooking, what you eat it with and your own body, so your meter or CGM is the best guide.
How grapes fit the plate method
Grapes count toward the carbohydrate quarter of the plate in the plate method, along with grains, starchy vegetables, fruit and milk. The CDC describes the plate method as half non-starchy vegetables, a quarter protein and a quarter carbohydrate foods. See the diabetic meal plan guide for how it works, or drop grapes onto a meal in the meal planner to watch the plate fill.
Portion ideas and pairings
- About 12 to 15 grapes is a typical snack portion.
- Put them in a bowl rather than eating from the bunch.
- Raisins are dried grapes and are far more concentrated.
Pairs well with: a piece of cheese, a few almonds or walnuts, plain yogurt.
Related foods
Banana
1 medium: 27 g carbs
Apple
cup, quartered or chopped: 17 g carbs
Strawberries
cup, halves: 12 g carbs
Watermelon
cup, balls: 12 g carbs
See all foods and the low glycemic foods list
Frequently asked questions
How many grapes can I eat?
The table shows carbohydrate for a cup and for 10 grapes. Your care team can tell you how many carbohydrate grams fit in a snack for you.
How many carbs are in a cup of grapes?
About 27 g of carbohydrate, of which about 1.4 g is fiber, so roughly 26 g net carbs. Values are from USDA FoodData Central for 151 g and are estimates; brands and sizes vary.
Information only, not medical advice. Your care team may set different targets for you, and only a lab test ordered by a clinician can diagnose diabetes or prediabetes. See our medical disclaimer.
Sources
- USDA FoodData Central: Grapes (FDC ID 174683)
- Atkinson FS et al. International tables of glycemic index and glycemic load values 2021. Am J Clin Nutr 2021;114(5):1625-1632
- CDC: Diabetes Meal Planning (plate method and carbohydrate counting)
- ADA Standards of Care in Diabetes—2026, Section 5: Facilitating Positive Health Behaviors
Last reviewed: by the Diabetes Blogs editorial team. Information only, not medical advice.
