Bok choy (pak choi) is a versatile leafy green that adds crunch, vitamins, and dietary fiber to stir-fries, soups, and salads. This calculator converts any amount of bok choy — grams, ounces, cups, or leaves — into its fiber content using the standard USDA reference value of about 1.0 g of fiber per 100 g of raw leaves. You can also flip it around: enter a daily fiber target and find out exactly how much bok choy you need to reach it.
Use amount-to-fiber mode when logging a meal, and fiber-goal mode when planning meals. The reference value is editable so you can match the fiber density printed on a specific product label. A quick preset row (100 g, 3 oz, 1 cup, 1 leaf) puts common servings one click away, and the result panel breaks down the math behind every answer.
🌿 Bok Choy Fiber Per 100g
Enter an amount and press Calculate.
Step-by-Step Guide
Fiber from amount. Choose the unit that matches how you measured your serving — grams, ounces, cups of chopped leaves, or whole large leaves. Enter the amount in the first field, or tap a preset button such as "100 g" or "1 cup" to fill it instantly. Leave the reference value at 1.0 g per 100 g unless you are using a specific label or database value, then click Calculate. The result panel shows the fiber grams, the conversion to raw weight, the multiplication step, and the percentage of a 25 g daily fiber target this serving provides.
Fiber goal → amount. Switch to the second mode by clicking "Fiber Goal → Amount." Enter the grams of fiber you want to reach in a meal or for the day, choose the unit you want the answer in from the unit dropdown, and press Calculate. The tool works out the raw weight of bok choy needed, then converts that weight into approximate cups of chopped bok choy and number of large leaves so you can picture the serving in practical terms.
Formula Explained
The calculator uses a simple proportion: fiber in grams equals (weight in grams × reference fiber per 100 g) ÷ 100. Since bok choy is mostly water, the reference value is small — the USDA standard is roughly 1.0 g of fiber per 100 g of raw leaves, but you can edit it.
Before applying the formula, the tool converts your chosen unit to grams. The conversion table used is based on typical raw weights: 1 oz = 28.35 g, 1 metric cup of chopped bok choy ≈ 70 g, and 1 large leaf ≈ 12 g. These are average kitchen estimates; your actual cup may be packed more or less tightly.
Worked example 1: A 170 g serving. 170 g × 1.0 g/100 g ÷ 100 = 1.7 g of fiber. That is about 7% of a 25 g target.
Worked example 2: Two cups of chopped bok choy. 2 cups × 70 g/cup = 140 g. 140 × 1.0 ÷ 100 = 1.4 g of fiber.
Worked example 3: Need 5 g of fiber from bok choy. 5 g × 100 ÷ 1.0 = 500 g, which is about 7 cups chopped or 42 large leaves.
Reference Values
The table below shows common serving sizes, their approximate raw weight, and the fiber they contribute at the standard reference value.
| Serving | Approx. raw weight | Fiber at 1.0 g/100 g |
|---|---|---|
| 100 g (≈ 1½ cups) | 100 g | 1.0 g |
| 1 cup chopped | 70 g | 0.7 g |
| 3 oz | 85 g | 0.85 g |
| 1 large leaf | 12 g | 0.12 g |
Because whole stems are denser than loose leaves, a cup of chopped bok choy can range from about 60 g to 80 g depending on how finely it is chopped and how firmly it is packed. Use these figures as planning estimates, not lab measurements.
Factors Affecting Accuracy
The fiber content of bok choy varies with the cultivar, growing conditions, maturity at harvest, and which parts of the plant you eat. The white, crunchy stems contain a little less fiber per gram than the dark green leaves, so a bag of baby bok choy may differ from fully mature heads. Different nutrition databases also round values differently; for example, the USDA lists raw bok choy at around 1.0 g fiber per 100 g, while some international databases report 1.1 to 1.2 g. This is why the reference field is editable — enter the exact per-100 g value printed on your product label or in your favorite nutrition app to get a closer match.
Frequently Asked Questions
Does cooking change the fiber content? No. Heat does not destroy dietary fiber, but cooking removes water, so cooked bok choy weighs noticeably less for the same amount of fiber. If you log cooked weights, the fiber per 100 g of cooked leaves will be higher — roughly 2 g per 100 g — simply because water is gone. For consistency, weigh bok choy raw whenever you can.
Is bok choy a good source of fiber? It is a light to moderate source: a typical one-cup serving supplies about 0.7 g, which is under 3% of an adult's daily target. It is more valuable for volume, vitamins A, C, and K, and antioxidants. To hit a 25 g daily fiber goal, combine it with higher-fiber foods such as oats, chickpeas, lentils, apples, or berries.
Why does this calculator's answer differ from my app? Differences come from the reference database, serving-size conventions, and whether the app counts soluble and insoluble fiber separately. The editable reference field lets you match your app's number: just enter its fiber-per-100 g value and recalculate.
Can I use this for baby bok choy or other leafy greens? You can, but the grams-per-cup and grams-per-leaf conversions may be different. For baby bok choy, a cup weighs less because the leaves are more loosely packed. For other greens like spinach or kale, both the weight per cup and the fiber density change, so check a reliable source such as USDA FoodData Central.
Tip: Weigh your bok choy on a kitchen scale when accuracy matters — a "cup" can vary by 20% or more depending on how it is chopped and packed.