Vegetable Serving Calculator
Calculate cups, grams, and ounces of 15 common vegetables per person or for a group.
Based on USDA cup serving sizes with per-serving calorie counts included.
One cup of vegetables sounds like a standard serving, but the weight varies enormously. A cup of spinach is 30 grams — barely an ounce. A cup of tomato is 180 grams. The volume is identical; the food is not.
This matters for meal planning because recipes give cups while nutrition databases list grams.
Why the weights differ so much
Texture and density. Raw spinach is mostly air pockets. Carrots are solid and dense. Corn kernels pack tightly. Sweet potato cubes settle. One cup of kale is a loose pile of leaves; one cup of peas is a fairly tight fill.
For practical cooking, 1 cup per person is a reasonable portion for most non-starchy vegetables. Corn, peas, and sweet potato are exceptions — they are calorie-dense and a half-cup is often more appropriate.
Calories per serving
Leafy greens and watery vegetables are very low: spinach (7 kcal/cup), zucchini (19 kcal/cup), cucumber (16 kcal/cup). You can eat large volumes without much caloric impact.
Starchy vegetables are different: corn (132 kcal/cup), peas (117 kcal/cup), sweet potato (114 kcal/cup). These are nutritionally valuable but need to be counted if you are tracking intake.
Meal planning rule of thumb
For side dishes: 1 cup raw per person for leafy greens (they cook down dramatically), or 0.5-0.75 cups for denser vegetables like broccoli and green beans. If a vegetable is the main component of a bowl or salad, 1.5-2 cups per person is more realistic.
The calorie numbers here are for raw vegetables. Roasting with oil or adding sauces changes the totals significantly — oil is 120 kcal per tablespoon. A roasted broccoli side drizzled with olive oil is closer to 80 kcal per cup than the raw 31 kcal.
This calculator scales linearly: double the servings, double the grams and calories.