About Units

Calories: Calories (cal) are a unit of energy. Specifically, they are defined as the amount of heat needed to raise the temperature of one gram of water by one degree Celsius. In nutrition, calories measure the energy content of food, with 1 food calorie (kcal) being equal to 1,000 small calories.

Watt hours: Watt-hours (Wh) are a unit of energy equivalent to one watt of power used for one hour. This unit is commonly used to measure electrical energy consumption. For example, household electrical energy usage is often measured in kilowatt-hours (kWh), where 1 kWh equals 1,000 Wh.