What is calorie (thermochemical)?

The thermochemical calorie is a unit of energy equal to approximately 4.184 joules. It is used in chemistry and physics to express small heat quantities, particularly in thermochemical experiments.

What is kilocalorie (dietary)?

A kilocalorie, written as Calorie with a capital C in nutrition contexts, is a unit of energy equal to 1,000 thermochemical calories. It is the standard unit used to express the energy content of food on nutrition labels globally.

Worked examples

1 calorie (thermochemical) = 0.001 kilocalorie (dietary)

1 kilocalorie (dietary) = 4,184 joule