Brussels sprouts are one of the most vitamin C-dense vegetables around: a raw 100 g serving (about 3.5 oz) provides roughly 85 mg of vitamin C, which is close to the full daily recommendation for many adults. This Brussels Sprout Vitamin C Calculator makes it easy to see exactly what your own serving delivers, whether you measure by grams, ounces, cups, or individual sprouts. It also adjusts for how you prepare them, because boiling and freezing change both the water content and the vitamin C concentration.
Enter a serving amount, pick the form of sprout, and choose a daily target to compare against. The tool calculates your vitamin C intake, the percentage of your target, and — if you want to plan ahead — how much you would need to eat to hit your goal. It is a practical companion for meal planning, diet logging, and any nutrient-focused eating plan.
🥦 Brussels Sprout Vitamin C Calculator
How to Use This Calculator
Start by selecting the form of brussels sprouts you're working with: raw, boiled/drained, or frozen. These forms differ in vitamin C concentration because cooking, freezing, and water loss all affect nutrient content. Boiling, for example, leaches vitamin C into the cooking water, while freezing can degrade some vitamin C over time. Next, enter how much you have in grams, ounces, cups, or whole sprouts — the tool converts everything to grams automatically using standard reference weights.
You can keep the daily target at 90 mg, switch it to 75 mg, or type in any personal goal. The result panel shows three useful numbers: your vitamin C intake in milligrams, the percentage of your daily target that serving covers, and how much you would need to eat to fully reach your goal in the same units you entered. Preset buttons load common portions such as '1 cup raw' or '3 oz boiled' so you can get an answer in one click.
Tip: U.S. recommendations are 75 mg per day for adult women and 90 mg per day for adult men. Smokers need about 35 mg more daily. If you're logging a whole meal rather than a single vegetable, remember that vitamin C also comes from citrus fruits, peppers, broccoli, and potatoes, so your total for the day adds up quickly.
How the Numbers Work
The calculator uses reference values from the USDA FoodData Central database:
- Raw brussels sprouts: about 84.8 mg vitamin C per 100 g
- Boiled, drained: about 62 mg per 100 g
- Frozen, unprepared: about 63 mg per 100 g
The core formula is: vitamin C (mg) = weight in grams ÷ 100 × mg per 100 g. For portion conversions, the tool assumes roughly 88 g per cup of raw or frozen sprouts, about 155 g per cup of boiled sprouts (denser because they absorb water during cooking), and about 19 g per medium sprout. One ounce equals 28.3495 g.
Worked example 1: You eat 150 g of raw sprouts. The calculation is (150 ÷ 100) × 84.8 = 127.2 mg. Against a 90 mg target, that is 141% of your daily need — a single generous serving nearly covers the whole day.
Worked example 2: You eat 6 medium boiled sprouts. Weight: 6 × 19 g = 114 g. Vitamin C: (114 ÷ 100) × 62 = 70.7 mg, which covers about 94% of a 75 mg target.
Worked example 3: To hit a 90 mg target with frozen sprouts, you need (90 ÷ 63) × 100 = 142.9 g, or roughly 1.6 cups of frozen sprouts.
Reference Table
| Form | Vitamin C per 100 g | Vitamin C per cup | Weight per cup |
|---|---|---|---|
| Raw | 84.8 mg | 74.6 mg | 88 g |
| Boiled, drained | 62.0 mg | 96.1 mg | 155 g |
| Frozen | 63.0 mg | 55.4 mg | 88 g |
Values are rounded for everyday use. Whole-food vitamin C content varies with variety, harvest season, storage duration, and cooking time, so treat the results as reliable estimates rather than exact lab measurements.
Common Mistakes to Avoid
- Using raw values after cooking. Boiling lowers vitamin C, so select the 'boiled' form when your sprouts are cooked. If you steam instead, losses are smaller — you can treat steamed sprouts as between raw and boiled values.
- Confusing weight ounces with fluid ounces. A kitchen scale is far more accurate than measuring cups for chopped sprouts, which pack differently depending on how finely they are shredded.
- Overlooking cooking water. Vitamin C leaches into the water when boiling. If you use that water for a sauce or soup, you recover some of the lost vitamin C.
- Assuming frozen equals raw. Frozen sprouts have slightly less vitamin C than fresh raw ones, and the loss grows with storage time, so use them within a few months.
Note: This tool provides nutrition estimates for informational purposes only and is not medical advice. If you have specific dietary needs or a medical condition, consult a registered dietitian or healthcare provider.
Frequently Asked Questions
Are boiled brussels sprouts still a good source of vitamin C? Absolutely. A cooked 100 g portion still provides about 62 mg, roughly 69% of the 90 mg adult male target and 83% of the 75 mg adult female target. Steaming causes fewer losses than boiling because less vitamin C leaches into the water, so choose steaming when you want to preserve nutrients.
Which form has the most vitamin C? Raw, shredded sprouts are the most concentrated at about 84.8 mg per 100 g — a great option for salads if you enjoy the texture. Since vitamin C is heat-sensitive and water-soluble, any cooking method that minimizes heat and water contact will preserve more of it.
Why is the default daily target 90 mg? That is the Recommended Dietary Allowance for adult men in the United States. Adult women have an RDA of 75 mg, pregnant women 85 mg, and breastfeeding women 120 mg. Smokers are advised to add 35 mg to their recommended intake because smoking increases oxidative stress and vitamin C turnover.
Sources
Reference values come from USDA FoodData Central (fdc.nal.usda.gov), and daily recommendations from the NIH Office of Dietary Supplements (ods.od.nih.gov). Both are authoritative, regularly updated sources for nutrient data and dietary guidance.