Knowing how many carbs are in vegetables is important for low-carb, keto, diabetic, and general macro-based eating plans. This calculator takes the guesswork out of serving sizes: choose a vegetable, enter your portion in grams, ounces, or cups, and instantly see total carbs, fiber, and net carbs. It uses per-100g carbohydrate values from USDA food-composition averages, so the numbers are realistic for typical raw, edible portions.
The menu covers 21 common vegetables including leafy greens, cruciferous vegetables, roots, nightshades, and starchy choices. Quick presets for 100g, 1 cup, and 1 medium piece let you estimate a serving without a scale, while the optional net-carbs toggle subtracts fiber for low-carb plans. The result panel shows the step-by-step math, so you understand exactly how each number was reached.
Whether you are portioning a side dish, logging a recipe, or planning a lower-carb plate, this quick reference helps you make consistent, informed choices.
📊 Results
How the Carb Math Works
The calculator applies a simple proportional formula. Each vegetable has a reference value expressed as grams of carbohydrate per 100 grams of raw, edible portion. Once your serving is converted to grams, the total is calculated as:
Total carbs = (serving weight in grams ÷ 100) × carbs per 100 g
The same scaling factor is applied to fiber, and net carbs, when the toggle is on, are total carbs minus fiber. A 150 g serving of raw broccoli contains 150 ÷ 100 = 1.5 portions of the reference value, so total carbs come to 1.5 × 6.6 = 9.9 g. The values in the menu are drawn from standard food-composition references such as USDA FoodData Central, which publishes nutrient averages for raw vegetables in common edible forms.
Because water content varies widely between vegetables, carb density is not a reliable predictor of how heavy a vegetable feels. A cup of spinach and a cup of carrots contain very different amounts of carbohydrate, which is exactly why a weight-based calculator gives more consistent macro tracking than visual estimates.
Step-by-Step Example: Broccoli
Example 1: 150 g of raw broccoli. Choose Broccoli (raw), enter 150 in the grams box, and press Calculate. The portion factor is 150 ÷ 100 = 1.50. Total carbs = 1.50 × 6.6 = 9.9 g. Fiber = 1.50 × 2.6 = 3.9 g. Net carbs = 9.9 − 3.9 = 6.0 g.
Example 2: one cup of raw spinach. A cup of raw spinach weighs about 30 g. Total carbs = 30 ÷ 100 × 3.6 = 1.1 g. Fiber = 30 ÷ 100 × 2.2 = 0.7 g, so net carbs are only 0.4 g. The result panel shows each step so you can verify the arithmetic.
Example 3: 4 oz of sweet potato. Four ounces equals 113.4 g. Total carbs = 1.134 × 20.1 = 22.8 g. Fiber = 1.134 × 3.0 = 3.4 g. Net carbs = 19.4 g.
Should You Count Net Carbs?
Fiber is listed as a carbohydrate on food labels because it is measured with the other carbs, but it is largely resistant to digestion. On a ketogenic or very low-carb diet, many people subtract fiber to estimate the carbohydrates that actually affect blood sugar. The net-carbs toggle in this calculator does that subtraction automatically.
Different low-carb programs define net carbs differently, and some also subtract sugar alcohols. Sugar alcohols are not included in this calculator, so if you are following a specific medical or therapeutic protocol, check its rules or consult a dietitian before relying on net-carb figures.
Carb Quick-Reference Table
Values below are per 100 g of raw, edible portion. The tool's dropdown contains the full list of 21 vegetables.
| Vegetable | Total carbs (g) | Fiber (g) | Net carbs (g) |
|---|---|---|---|
| Spinach | 3.6 | 2.2 | 1.4 |
| Broccoli | 6.6 | 2.6 | 4.0 |
| Cauliflower | 5.0 | 2.0 | 3.0 |
| Cucumber | 3.6 | 0.5 | 3.1 |
| Carrot | 9.6 | 2.8 | 6.8 |
| Green peas | 14.5 | 5.7 | 8.8 |
| Sweet corn | 19.0 | 2.0 | 17.0 |
| Avocado | 8.5 | 6.7 | 1.8 |
Tips for Low-Carb Vegetable Choices
- Leafy greens such as spinach, kale, and lettuce deliver the fewest carbs per serving and make a great base for low-carb plates.
- Use the 1 cup preset only as a rough guide. Cup weights vary with chopping and packing; weighing your portion once with a kitchen scale calibrates your eye for later estimates.
- Starchy vegetables like potato, corn, and green peas are nutritious but higher in carbs, so keep portions smaller on lower-carb plans.
- Preparation changes the numbers. Roasting or boiling drives off water and concentrates carbs per gram, so the raw values here should not be applied directly to cooked weights.
Limitations & Precision Notes
Carbohydrate values are averages from national food databases. Real produce varies by variety, season, ripeness, and growing conditions, and differences of 10–15% are common between samples.
The medium and cup presets are approximate conversions. A medium potato or avocado can vary by 30 g or more, so weigh your food in grams for precise macro tracking. Results are rounded to one decimal place, which is appropriate for practical meal planning.
Frequently Asked Questions
Are these values for raw or cooked vegetables? All menu values are for raw, edible portions. Cooking reduces weight through water loss, so 100 g of cooked vegetables contains more carbohydrate per gram than 100 g raw. If you log cooked food, use a cooked-value source.
Why does a vegetable have more carbs than I expected? The total includes fiber, starch, and natural sugars. Sweet corn and peas are starchy, and even carrots contain more natural sugar than leafy greens. Total carbs give a fuller picture than a simple sweet-versus-savory rule of thumb.
Can I use this for a diabetic meal plan? Yes, and the total-carb figure is the one most closely tied to blood sugar response. Individual responses vary, so pair the numbers with your own glucose monitoring and discuss meal planning with your healthcare team.
Where do the base values come from? Per-100g figures are based on USDA FoodData Central entries for raw vegetables, one of the most widely used public food-composition references. You can browse the original data at the USDA FoodData Central website.