Kilocalorie (kcal) to Kilojoule

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Result

4.184

kJ

Conversion rate: 1 kcal = 4.184 kJ

Showing up to 4 decimal

How it works

The converter uses exact SI-based factors (e.g., 1 foot = 0.3048 meters, 1 inch = 0.0254 meters).

Formula: kilojoules = kilocalorie (kcal) × 4.184

Results show between 0 and 8 decimal places and hide trailing zeros for readability.

Conversion Table

Kilocalorie (kcal) Kilojoule
1 kcal 4.184 kJ
10 kcal 41.84 kJ
100 kcal 418.4 kJ
1000 kcal 4184 kJ
1000000 kcal 4184000 kJ

History

Kilocalorie (kcal)

The kilocalorie, symbolized as kcal, equals 1,000 calories and is often referred to as a “Calorie” with a capital C in food labeling. It measures the energy in food and human metabolism, helping dieticians, nutritionists, and consumers track intake. The kilocalorie became the standard unit of energy measurement as nutrition science linked energy measurement to diet. Most scientists now use joules, but kilocalories are still commonly used in reporting food energy.

Kilojoule (kJ)

The kilojoule, symbol kJ, equals 1,000 joules and is used for measuring larger quantities of energy. It was introduced to simplify calculations in nutrition, physics, and engineering, where joules alone would result in very large numbers. Kilojoules are commonly used to express the energy content of foods, fuel consumption, and industrial energy usage. The adoption of the kilojoule has standardized energy measurements across scientific disciplines and commercial applications, offering clarity and ease of use in both everyday and professional contexts.

Other Relevant Conversions

J → kJ J → cal J → kcal J → Wh J → kWh J → eV J → BTU kJ → J kJ → cal kJ → kcal kJ → Wh kJ → kWh kJ → eV kJ → BTU cal → J cal → kJ cal → kcal cal → Wh cal → kWh cal → eV cal → BTU kcal → J kcal → kJ kcal → cal kcal → Wh kcal → kWh kcal → eV kcal → BTU Wh → J Wh → kJ Wh → cal Wh → kcal Wh → kWh Wh → eV Wh → BTU kWh → J kWh → kJ kWh → cal kWh → kcal kWh → Wh kWh → eV kWh → BTU eV → J eV → kJ eV → cal eV → kcal eV → Wh eV → kWh eV → BTU BTU → J BTU → kJ BTU → cal BTU → kcal BTU → Wh BTU → kWh BTU → eV