Watercress is one of the lowest-calorie leafy greens you can add to salads, sandwiches, and smoothies — a full chopped cup typically provides only about 4 kcal. This calculator converts any amount of raw watercress into its calorie value, using USDA nutrition data for raw watercress (roughly 11 kcal per 100 g, or 34 g per chopped cup).
It also breaks down protein, carbohydrate, fiber, and fat, plus standout micronutrients such as vitamin K and vitamin C. Because watercress is so light, calorie numbers are small, but the calculator helps you track them accurately for meal planning, calorie-controlled diets, or macro tracking.
Use the amount field and unit selector (cups, tablespoons, grams, or 100 g portions), or click a quick-fill preset to estimate a typical serving in one tap.
🥬 Watercress Energy Calculator
Estimate calories, macros, and key micronutrients for raw watercress.
Step-by-Step Guide
Estimate watercress calories in seconds:
- Enter the amount in the number field. If you know the volume in cups, keep the unit set to "cups, chopped"; choose tablespoons, grams, or 100 g portions instead when that matches your recipe.
- Click one of the quick-fill buttons to load a common serving — 1 cup, ½ cup, 1 tablespoon, or 100 g.
- Press Calculate to see total calories, macronutrients, vitamin C and vitamin K, plus the conversion step.
The calculator uses the U.S. Department of Agriculture's standard values for raw watercress: about 11 kcal per 100 g and 34 g per chopped cup. Because watercress is mostly water, the energy numbers are tiny — that is normal and correct.
Nutrition Reference Table
These values are based on raw, fresh watercress as listed in the USDA FoodData Central database. A "cup" here means a measuring cup of loosely packed chopped leaves and stems, weighing about 34 g.
| Nutrient | Per 100 g | Per 1 cup (34 g) |
|---|---|---|
| Calories | 11 kcal | 3.7 kcal |
| Protein | 2.3 g | 0.8 g |
| Carbohydrate | 1.3 g | 0.4 g |
| Fiber | 0.5 g | 0.2 g |
| Fat | 0.1 g | <0.1 g |
| Vitamin C | 43 mg | 14.6 mg |
| Vitamin K | 250 mcg | 85 mcg |
Full nutrient detail is available from USDA FoodData Central. The database also includes values for cooked or prepared watercress if your recipe calls for a different form.
Worked Examples
Example 1: 1.5 cups of chopped watercress. Multiply 1.5 by 34 g to get 51 g. Then multiply 51 by 0.11 kcal/g: 5.6 kcal. The same serving provides about 1.2 g protein and 0.7 g carbohydrate — a very light base for a large salad.
Example 2: A 25 g handful. A small handful typically weighs around 25 g. Calories: 25 × 0.11 = 2.8 kcal. Toss two handfuls into a sandwich or omelet and you still add well under 10 kcal while contributing 43–50 mcg of vitamin K and a useful hit of vitamin C.
Notice how consistent the calorie yield is: one full cup rarely exceeds 4 kcal. This is why watercress appears in nearly every "free vegetable" list for calorie-controlled eating plans.
Why Watercress Is So Low in Calories
Watercress is about 95% water by weight, as Wikipedia's watercress entry notes in its nutritional summary. The remaining solids are largely fiber, protein, and micronutrients, with almost no starch or fat. Because energy density is only about 0.11 kcal per gram, even a generous 100 g portion has fewer calories than a single small strawberry.
That does not mean it is nutritionally empty. Watercress is a Brassica crop in the same family as kale, cabbage, and arugula, and it is consistently ranked among the most nutrient-dense vegetables.
Micronutrient Highlights
One chopped cup of raw watercress provides roughly:
- 85 mcg of vitamin K — about 70% of the Daily Value used in the United States.
- 14.6 mg of vitamin C — close to 15% of the Daily Value.
- about 54 mcg RAE of vitamin A from beta-carotene.
- 34 mg of calcium, plus small amounts of iron, magnesium, potassium, and folate.
Vitamin K is essential for blood clotting and bone health; the National Institutes of Health publishes an evidence-based vitamin K fact sheet with more detail on recommended intakes.
People taking blood-thinning medications such as warfarin should keep their vitamin K intake consistent and talk with a clinician before dramatically increasing leafy greens like watercress.
Measuring Tips & Common Mistakes
- Use the chopped-cup standard. A cup of whole, untrimmed sprigs weighs less than a chopped cup. This calculator is calibrated for chopped, loosely packed leaves and stems.
- Do not press watercress into the cup. Firmly packed greens can nearly double the weight and therefore the calories.
- Weigh when accuracy matters. If you are tracking macros strictly, a kitchen scale is more reliable than a measuring cup. The gram and 100 g portion options in the calculator are designed for that.
- Do not log watercress as zero. It is low, but not literally zero, and the small amount of protein, fiber, and vitamin K is worth recording in a food diary.
- Consider stems. The tender stems are edible and included in the USDA nutrient values; trim only thick, tough lower stems.
Frequently Asked Questions
Is watercress really only about 4 calories per cup? Yes, for a standard 34 g chopped cup of raw watercress, the USDA value is approximately 4 kcal. Individual bunches vary slightly with water content and maturity, but the calorie range is 3–5 kcal per cup.
Does cooking change the calorie count? Boiling watercress reduces its volume but does not add calories. The nutrient values change slightly because water and some water-soluble vitamins leach into the cooking liquid; the calories remain very close to the raw value per gram of dry matter.
Can I replace salad greens with watercress to cut calories? Yes. A cup of shredded romaine has about 8 kcal and a cup of iceberg lettuce about 10 kcal, so watercress is even lighter while delivering more vitamin K and vitamin C.
Why does my food tracker show a different number? Apps may use different serving definitions, such as per sprig, per cup, or per bunch. Check whether the tracker assumes chopped or whole leaves; the cup values differ because the same volume weighs a different amount.