Calorie Density Calculator
Work out a food's calorie (energy) density in kcal per gram from its label, classify it from very low to high as in the Volumetrics approach, and see how much you can eat for 100 or 500 kcal.
How it works
calorie density = calories ÷ weight in grams (kcal/g) · very low < 0.6, low 0.6–1.5, medium 1.5–4, high > 4 kcal/g
Calorie density (energy density) is how many calories a food packs into each gram. Barbara Rolls's research at Penn State, popularised as the Volumetrics plan, showed that people tend to eat a similar weight of food from day to day, so choosing foods with lower energy density lowers calorie intake without smaller portions. Water and fibre lower energy density; fat raises it most, at 9 kcal per gram.
Worked example
A 200 g serving with 250 kcal has a calorie density of 250 ÷ 200 = 1.25 kcal/g — a low-density food. 100 g gives 125 kcal, and you could eat 80 g for 100 kcal or 400 g for 500 kcal.
Sources: Rolls BJ. The relationship between dietary energy density and energy intake. Physiol Behav 2009
Frequently asked questions
What is a good calorie density for weight loss?
Aim for most of your plate to be below about 1.5 kcal/g (very low and low categories) — vegetables, fruit, soups, lean proteins, legumes and whole grains — and keep high-density foods to small portions.
How do I find calorie density from a label?
Divide the calories per serving by the serving size in grams. If the label shows "per 100 g", simply divide that calorie figure by 100.
Are high-calorie-density foods unhealthy?
Not necessarily — nuts, olive oil and avocado are energy dense but nutritious. Density helps with portion control; nutrient quality is a separate question.
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This calculator is for educational purposes. Double-check important results before acting on them.