Choy — a family of leafy Asian greens including bok choy, choy sum, napa cabbage, and gai choy — is among the lowest-carb vegetables you can add to a meal. This calculator shows the carbohydrates per 100 grams of your chosen choy variety and converts that to the actual amount on your plate. Select a variety, enter your serving in grams or ounces, and get total carbs, net carbs, fiber, and sugar at a glance. It is designed for keto and low-carb trackers, meal planners, recipe logging, and anyone curious about the nutrition of leafy greens. Because varieties differ — napa cabbage runs slightly higher in carbs than bok choy, while gai choy is richer in fiber — you can also compare them side by side.
Values are based on USDA reference data and rounded to the nearest 0.1 g for everyday tracking. For precise medical or clinical decisions, check the nutrition label on your actual product or consult a registered dietitian.
🥬 Choy Carbs per 100 g Calculator
Total carbs, net carbs, fiber, and sugar for your exact serving size.
Quick Start
Pick the choy variety that matches what you are weighing, enter the amount, and hit Calculate. The presets (50 g, 1 cup, 100 g, 6 oz) are handy when you are measuring raw leafy greens loosely rather than on a scale. If you switch between grams and ounces, the calculator converts automatically — 1 ounce equals 28.35 g.
How the Math Works
Every choy entry in the calculator is assigned three USDA-style values per 100 g: total carbohydrates, dietary fiber, and sugar. The calculator scales each value to your serving using the same simple proportion. If your serving is 150 g, the per-100 g value is multiplied by 1.5; if it is 40 g, it is multiplied by 0.4. This works for any serving size, whether you are logging a light side dish or a large soup portion.
Example 2: Napa cabbage raw contains 3.2 g carbs per 100 g. For a 200 g serving: 3.2 × 2 = 6.4 g total carbs, 1.0 × 2 = 2.0 g fiber, net carbs = 4.4 g.
Net carbs are calculated only as total minus fiber, which is the convention most low-carb trackers use. Some labels may report net carbs differently by also subtracting sugar alcohols or using different fiber definitions, so compare methods if you are logging precisely for a specific diet plan.
Reference Table
| Variety | Carbs (g/100g) | Fiber (g/100g) | Sugar (g/100g) |
|---|---|---|---|
| Bok choy, raw | 2.2 | 1.0 | 1.2 |
| Bok choy, boiled | 1.8 | 1.0 | 0.8 |
| Choy sum / yu choy | 2.6 | 1.5 | 1.2 |
| Gai choy (mustard) | 4.9 | 2.0 | 2.6 |
| Napa cabbage | 3.2 | 1.0 | 1.4 |
| Tatsoi | 2.0 | 1.4 | 0.8 |
Values are rounded from USDA food composition sources and can vary by cultivar, growing conditions, maturity, and cooking method. For the most up-to-date full database, visit USDA FoodData Central.
Tips & Best Practices
- Weigh greens raw before cooking — water loss after cooking concentrates nutrients per gram, so cooked weights will give slightly different numbers.
- Buy pre-cut choy? Use the same per-100 g values; just weigh your actual portion instead of estimating by handfuls.
- For keto or very low-carb targets, remember that choy fiber counts toward your daily fiber goal, which many people find helpful for digestion and satiety.
- When a variety differs from the list, choose the closest match and check the package label if one is available.
- If you log by cooked weight, prefer the boiled bok choy row for a closer match to water-loss-adjusted nutrition.
Accuracy & Limitations
The numbers in this calculator come from standard USDA reference entries, but real-world produce is not perfectly uniform. A bok choy grown in one season may test slightly different from another. The calculator rounds to one decimal place, which is enough for daily tracking but not for clinical meal planning. If you are following a medically prescribed carbohydrate limit, use the nutrition label on the actual product whenever possible and confirm portions with a food scale.
FAQ
Is choy keto-friendly? Yes. Even the highest-carb choy here (gai choy at 4.9 g per 100 g) fits easily into a 20–50 g daily carb budget. A typical 100 g serving of bok choy provides just 2.2 g total carbs and about 1.2 g net carbs.
Should I use raw or cooked values? Use raw values when logging the amount you put in the pan. If you log by cooked weight, the boiled bok choy row is a closer match because cooking reduces weight by roughly 30–40% while the carb content stays in the smaller mass.
Why is net carbs lower than total carbs? Net carbs subtract fiber because fiber is not digested and absorbed the same way as other carbohydrates. This calculator uses total carbs minus fiber, without subtracting sugar alcohols, which are rare in fresh leafy greens.
Why does the calculator show the same fiber and sugar for several varieties? Many leafy greens share similar macronutrient profiles. USDA reference values are rounded, and small differences in fiber or sugar are often within natural variation between samples.