Convert Kilojoules to Kilocalories
Instantly convert Kilojoules (kJ) to Kilocalories (kcal) with our free online calculator.
Formula: kJ to kcal — multiply by 0.239006
Reference Table
| Kilojoules (kJ) | Kilocalories (kcal) |
|---|---|
| 1 | 0.239006 |
| 5 | 1.19503 |
| 10 | 2.39006 |
| 25 | 5.97514 |
| 50 | 11.9503 |
| 100 | 23.9006 |
How to Convert Kilojoules to Kilocalories
Formula
To convert Kilojoules (kJ) to Kilocalories (kcal): multiply by 0.239006
Step-by-Step
- Start with your value in Kilojoules (kJ).
- Multiply by 0.239006 to perform the conversion.
- The result is your value expressed in Kilocalories (kcal).
Conversion Factor
1 kJ = 0.239006 kcal
Reverse Factor
1 kcal = 4.184 kJ
Worked Example
Convert 25 Kilojoules to Kilocalories: 25 kJ = 5.97514 kcal
About Kilojoule (kJ)
A metric unit of energy equal to exactly 1,000 joules. Kilojoules are the working unit for food-energy labelling outside the United States — Australia and New Zealand display kJ-only nutrition panels per FSANZ standards 1.2.7 / 1.2.8, the European Union requires kJ alongside kcal per EU Regulation 1169/2011, and Codex Alimentarius (the international food labelling standard) uses kJ. Reference values: a Big Mac is ~2,220 kJ, an adult daily energy intake is 8,000-10,500 kJ (about 2,000-2,500 kcal) per WHO/FAO Recommended Dietary Allowances, a 350 mL soft drink ~600 kJ. The kJ is also the natural engineering unit for small-scale mechanical work (joules per stroke on a punch press), small-cell battery capacity (e.g., a smartphone Li-ion at ~40 kJ), and small-scale thermodynamic calculations like an espresso machine's per-shot energy budget (~20 kJ). 1 kJ = 0.2389 kcal = 0.948 BTU = 277.8 mWh.
About Kilocalorie (kcal)
A unit of energy equal to exactly 1,000 gram-calories (= exactly 4,184 joules per the thermochemical definition). This is the unit behind the 'Calorie' (capital C) on US food packaging — a 200-Calorie granola bar contains 200 kcal = 200,000 small calories = 836 kJ. Adult daily dietary intake per FDA / USDA Dietary Guidelines is 1,600-2,400 kcal for women and 2,000-3,000 kcal for men depending on age and activity, with WHO baseline targets of 2,000 / 2,500 kcal. Indirect calorimetry (gold-standard metabolic rate measurement) reports BMR / TDEE in kcal/day. Kilocalories are also used for refrigeration / heating-system output in some legacy European industrial specifications (kcal/h sometimes appears on older boilers and chillers, though kW has largely replaced it), and for muscle-physiology energy-expenditure reporting in exercise science. The 'Atwater system' (4-9-4 macronutrient values: 4 kcal/g protein, 9 kcal/g fat, 4 kcal/g carbohydrate) is the calculation method behind almost every nutrition label.
Quick Facts
- 1 Kilojoule equals 0.239006 Kilocalories
- 1 Kilocalorie equals 4.184 Kilojoules
- Kilojoule is a unit of energy
- Kilocalorie is a unit of energy
- This conversion is commonly used in nutrition, electrical billing, physics, and mechanical engineering
- The Kilojoule belongs to the metric system
Common Kilojoule to Kilocalorie Conversions
| Kilojoules (kJ) | Kilocalories (kcal) |
|---|---|
| 0.01 | 0.00239006 |
| 0.1 | 0.0239006 |
| 0.25 | 0.0597514 |
| 0.5 | 0.119503 |
| 1 | 0.239006 |
| 2 | 0.478011 |
| 3 | 0.717017 |
| 5 | 1.19503 |
| 10 | 2.39006 |
| 15 | 3.58509 |
| 20 | 4.78011 |
| 25 | 5.97514 |
| 50 | 11.9503 |
| 75 | 17.9254 |
| 100 | 23.9006 |
| 250 | 59.7514 |
| 500 | 119.503 |
| 1000 | 239.006 |
| 5000 | 1195.03 |
| 10000 | 2390.06 |
Understanding Kilojoules
The Kilojoule (symbol: kJ) is a unit of energy. A metric unit of energy equal to exactly 1,000 joules. Kilojoules are the working unit for food-energy labelling outside the United States — Australia and New Zealand display kJ-only nutrition panels per FSANZ standards 1.2.7 / 1.2.8, the European Union requires kJ alongside kcal per EU Regulation 1169/2011, and Codex Alimentarius (the international food labelling standard) uses kJ. Reference values: a Big Mac is ~2,220 kJ, an adult daily energy intake is 8,000-10,500 kJ (about 2,000-2,500 kcal) per WHO/FAO Recommended Dietary Allowances, a 350 mL soft drink ~600 kJ. The kJ is also the natural engineering unit for small-scale mechanical work (joules per stroke on a punch press), small-cell battery capacity (e.g., a smartphone Li-ion at ~40 kJ), and small-scale thermodynamic calculations like an espresso machine's per-shot energy budget (~20 kJ). 1 kJ = 0.2389 kcal = 0.948 BTU = 277.8 mWh.
It belongs to the metric measurement system.
Kilojoules are commonly used in nutrition, electrical billing, physics, and mechanical engineering.
Understanding Kilocalories
The Kilocalorie (symbol: kcal) is a unit of energy. A unit of energy equal to exactly 1,000 gram-calories (= exactly 4,184 joules per the thermochemical definition). This is the unit behind the 'Calorie' (capital C) on US food packaging — a 200-Calorie granola bar contains 200 kcal = 200,000 small calories = 836 kJ. Adult daily dietary intake per FDA / USDA Dietary Guidelines is 1,600-2,400 kcal for women and 2,000-3,000 kcal for men depending on age and activity, with WHO baseline targets of 2,000 / 2,500 kcal. Indirect calorimetry (gold-standard metabolic rate measurement) reports BMR / TDEE in kcal/day. Kilocalories are also used for refrigeration / heating-system output in some legacy European industrial specifications (kcal/h sometimes appears on older boilers and chillers, though kW has largely replaced it), and for muscle-physiology energy-expenditure reporting in exercise science. The 'Atwater system' (4-9-4 macronutrient values: 4 kcal/g protein, 9 kcal/g fat, 4 kcal/g carbohydrate) is the calculation method behind almost every nutrition label.
Kilocalories are commonly used in nutrition, electrical billing, physics, and mechanical engineering.
Why Convert Kilojoules to Kilocalories?
Converting energy between Kilojoules and Kilocalories is common in physics, nutrition, and engineering. Electricity bills use kilowatt-hours, food labels list calories or kilojoules, and mechanical engineers work with joules and BTUs. Reliable conversion helps professionals and consumers compare energy values across different contexts.
Frequently Asked Questions
How do I convert Kilojoules to Kilocalories?
A metric unit of energy equal to exactly 1,000 joules. To convert Kilojoules to Kilocalories, multiply by 0.239006. For example, 25 kJ equals 5.97514 kcal.
How many Kilocalories are in 1 Kilojoule?
There are 0.239006 Kilocalories in 1 Kilojoule.
How many Kilojoules are in 1 Kilocalorie?
There are 4.184 Kilojoules in 1 Kilocalorie.
What is the formula for Kilojoule to Kilocalorie conversion?
The formula is: multiply by 0.239006. This means 1 kJ = 0.239006 kcal.
Is a Kilojoule bigger than a Kilocalorie?
Yes. One Kilojoule is larger than one Kilocalorie because 1 kJ equals 0.239006 kcal, which is less than 1.
When do you need to convert between Kilojoules and Kilocalories?
A unit of energy equal to exactly 1,000 gram-calories (= exactly 4,184 joules per the thermochemical definition). Kilojoule and Kilocalorie are both energy units, so conversion comes up whenever one source of information uses one unit and another uses the other — a classic cross-reference challenge in engineering, trade, travel, and everyday life.