Spaghetti squash is low in carbs. One cup (155 grams) of cooked spaghetti squash contains about 10 grams of total carbohydrates and 2.2 grams of fiber, putting the net carbs at roughly 7.8 grams per serving. That’s a fraction of what you’d get from regular pasta, which packs around 43 grams of carbs in the same cooked cup.
How It Compares to Regular Pasta
The reason most people search this question is because they’re considering spaghetti squash as a swap for traditional noodles. The numbers make a strong case. A cup of cooked spaghetti squash has 42 calories and 10 grams of carbs. A cup of cooked semolina pasta has roughly 220 calories and 43 grams of carbs. That’s about 75% fewer carbs and 80% fewer calories for essentially the same volume on your plate.
The texture isn’t identical to wheat pasta, but when you scrape a fork along the inside of a cooked spaghetti squash, the flesh separates into long, noodle-like strands that hold sauce reasonably well. It won’t fool anyone into thinking they’re eating linguine, but it works as a base for marinara, pesto, or meat sauce without the carb load.
Net Carbs and Keto Compatibility
If you’re tracking net carbs for a ketogenic or other low-carb diet, spaghetti squash fits comfortably into most plans. With roughly 7.8 grams of net carbs per cup, a generous serving uses up less than half of a strict 20-gram daily keto limit and well under a quarter of a more moderate 50-gram target. That leaves plenty of room for toppings, protein, and other vegetables in the same meal.
Compare that to other popular squash varieties. Butternut squash has about 16 grams of net carbs per cup, and acorn squash runs around 20 grams. Among winter squashes, spaghetti squash is one of the lowest-carb options available.
Blood Sugar Impact
Spaghetti squash has a low glycemic index, meaning it raises blood sugar more slowly than high-carb foods like white bread or regular pasta. Its glycemic load, which accounts for both the speed of blood sugar rise and the actual amount of carbs in a serving, falls in the medium range. For most people, this translates to a modest, gradual blood sugar response rather than a sharp spike and crash.
The fiber content plays a role here. At 2.2 grams per cup (some measurements put it closer to 3 grams depending on the density of the serving), fiber slows digestion and helps blunt the blood sugar effect of whatever carbohydrates are present. It’s not a high-fiber food by any stretch, but the combination of low total carbs and moderate fiber keeps the glycemic impact mild.
What Else You Get Nutritionally
Spaghetti squash isn’t just a low-carb stand-in. At 42 calories per cup, it’s one of the lightest vegetable bases you can build a meal around. It provides meaningful amounts of vitamin C, vitamin B6, and manganese. The water content is high, which contributes to the low calorie count and helps you feel full on a relatively large volume of food. If your goal is to eat a big, satisfying plate without a heavy calorie or carb cost, spaghetti squash delivers on that front better than most alternatives.
Portion Size Matters
One thing to keep in mind: a whole spaghetti squash yields several cups of strands. A medium squash typically produces 3 to 4 cups once cooked and scraped. If you eat half a squash in one sitting, you’re looking at closer to 15 to 20 grams of total carbs. That’s still dramatically less than a comparable portion of pasta, but it’s worth measuring if you’re counting precisely for a keto or diabetic meal plan.
The simplest cooking method is to halve the squash lengthwise, scoop out the seeds, and roast it cut-side down at 400°F for about 35 to 45 minutes until the flesh is tender. Then drag a fork across the inside to pull the strands free. One cup of those strands, loosely packed, is 155 grams, the standard serving size you’ll see on most nutrition references.