Direct answer

Calorie vs Kilocalorie: What’s the Difference?

On food labels, “Calorie” usually means kilocalorie (kcal). Small calorie (cal) vs food Calorie explained with conversion links.

Question

What is the difference between a calorie and a kilocalorie?

1 kilocalorie (kcal) = 1,000 small calories (cal). Food-label “Calories” almost always mean kilocalories.

1 kcal

1,000 cal

1 cal

≈ 4.184 J

1 kcal

≈ 4,184 J

Food “Calorie”

Usually means 1 kcal

In physics, 1 calorie (cal) is about 4.184 joules. A kilocalorie is 1,000 of those small calories.

Nutrition labels capitalize “Calorie” or say kcal to mean the food energy unit people track daily.

So a 200 Calorie snack is 200 kcal, not 200 small calories.

Important caveat

Always check whether a scientific source means small calorie (cal) or food kilocalorie (kcal / Cal).