Bok choy — also called pak choi or Chinese white cabbage — is a leafy green that appears in stir-fries, soups, and side dishes. It is low in calories but supplies a modest amount of plant protein along with vitamin K, vitamin C, and folate. A 100-gram serving of raw bok choy contains about 1.5 grams of protein and only 13 calories, making it a useful way to add volume and micronutrients without blowing your macronutrient targets.
This Bok Protein Calculator helps you find the protein in your serving using grams or common kitchen measures like chopped cups or handfuls. You can switch between raw and cooked bok choy, and optionally set a daily protein target to see what percentage of your goal one serving covers. Whether you are meal-prepping, tracking macros, or just curious, this tool gives you a quick, reliable answer in seconds.
🥬 Bok Protein Calculator
Estimate the protein in your serving of bok choy — raw or cooked.
How to Use This Tool
Using the calculator takes four simple steps. First, enter the amount of bok choy you plan to log in the serving amount field. You can type a number like 150 for grams, 2 for cups, or 3 for handfuls. Second, choose the matching unit from the dropdown so the tool knows whether your number means grams, chopped cups, or handfuls. Third, select whether your bok choy is raw or boiled, because cooking changes the water content and therefore the protein density by weight. Finally, if you track your daily intake, enter a target such as 120 g of protein per day. Click Calculate and the result area shows the protein from your serving and, when a target is given, the percentage of that target the serving covers. Reset clears everything and restores the default values.
How the Calculation Works
The tool applies a simple proportional formula: protein (g) = serving weight (g) × protein per 100 g ÷ 100. Serving weight is first converted from the unit you selected. One chopped cup of raw bok choy weighs about 70 g, and a handful is estimated at 50 g. The protein factor is 1.50 g per 100 g for raw bok choy and 1.56 g per 100 g for boiled, drained bok choy, based on USDA FoodData Central values. For example, 200 g of raw bok choy contains 200 × 1.50 ÷ 100 = 3.00 g of protein. This is the same logic used by most nutrition tracking apps, which store per-100-gram values and scale them to your portion.
Worked Examples
Example 1: You add 2 cups of chopped raw bok choy to a stir-fry. Two cups equals 140 g (2 × 70). Protein = 140 × 1.50 ÷ 100 = 2.10 g. If your daily target is 120 g, that is 2.10 ÷ 120 × 100 = 1.75% of your goal.
Example 2: You serve yourself 3 handfuls of raw bok choy in a salad. Three handfuls equals 150 g (3 × 50). Protein = 150 × 1.50 ÷ 100 = 2.25 g.
Example 3: You weigh 180 g of boiled bok choy after draining. Using the cooked factor, protein = 180 × 1.56 ÷ 100 = 2.81 g. Notice the cooked value per 100 g is slightly higher than raw because water has evaporated, concentrating the nutrients.
Reference Table: Bok Choy per 100 g
The table below shows average nutrient values for raw and boiled bok choy. Use it to check your servings against other leafy greens.
| Nutrient | Raw | Boiled (drained) |
|---|---|---|
| Protein | 1.50 g | 1.56 g |
| Energy | 13 kcal | 12 kcal |
| Carbohydrates | 2.18 g | 1.78 g |
| Fiber | 1.0 g | 1.0 g |
| Vitamin C | 45 mg | 34 mg |
| Folate | 66 µg | 49 µg |
Values are from the USDA FoodData Central database and represent averages for common varieties of bok choy. Actual values depend on the cultivar, season, and how the vegetable is prepared.
Factors Affecting Accuracy
Nutrition facts are never exact for fresh produce. Protein content can vary by variety, soil, maturity, and how long the bok choy is stored before cooking. Volume-based measures are the biggest source of error: a cup of chopped bok choy can weigh anywhere from 55 g to 85 g depending on how finely you chop it and how tightly you pack the cup. The handful estimate of 50 g is especially rough because hand size differs between individuals. Cooking also changes weight dramatically — boiled bok choy retains less water and may weigh less while having a slightly higher protein density. For precise macro tracking, weigh raw bok choy on a kitchen scale and use the raw setting. This tool is designed for meal planning and general guidance, not medical or clinical use.
Practical Tips
- Weigh bok choy raw before cooking — that is the most consistent reference point for your food diary.
- If you only weighed the cooked portion, choose “cooked” in the preparation dropdown to avoid under- or overestimating.
- Combine bok choy with a complete protein source such as tofu, chicken, fish, or eggs to round out the amino acid profile.
- Use bok choy to add volume and micronutrients to meals while barely affecting calorie totals — a 100 g serving has only about 13 kcal.
- When meal prepping, estimate the total batch weight and divide by portions so your per-serving calculation stays accurate.
Frequently Asked Questions
Does cooking increase the protein in bok choy? Cooking does not create protein; it removes water, so a 100 g portion of boiled bok choy contains slightly more protein per gram than raw. A whole vegetable has roughly the same total protein before and after cooking, assuming no protein is lost in the cooking water.
Is bok choy a good protein source? Bok choy is low in protein compared with beans, tofu, or meat. One cup of raw, chopped bok choy provides about 1.05 g of protein. It is valuable mainly as a low-calorie vegetable that contributes a little protein while delivering vitamins and fiber.
Should I log raw or cooked weight? Nutrition labels and databases typically list raw values, so weighing before cooking and selecting raw is usually more accurate. If you weigh later, use cooked values and the cooked setting on this calculator.