kcal
abbreviation
kilocalorie(s), kilogram calorie(s).
"The large calorie, kilogram calorie or food calorie (symbol: Cal)[2] approximates the energy needed to increase the temperature of 1 kilogram of water by 1 °C. This is exactly 1000 small calories or about 4.2 kilojoules." - from wiki
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In nutritional contexts, however, the small calorie is too small a unit to be useful; so the term calorie is used for the large calorie, as is the equivalent term kilocalorie (symbol: kcal), being 1000 small calories = 1 large calorie.[2] Therefore, in nutritional contexts calorie and kilocalorie are the same size.