Convert Calories (cal) to Kilojoules (kJ)

1 cal = 0.004 kJ

How many Kilojoules in a Calorie?Printable chart →

Converting calories to kilojoules is essential for understanding energy content in food and exercise. With the conversion factor of 1 cal = 0.004184 kJ, you can easily translate energy measurements. This is particularly useful for those tracking their dietary intake or energy expenditure.

Calorie (cal)

Kilojoule (kJ)

0.004184

Conversion Formula

kJ = cal × 0.004184

Reverse: cal = kJ × 239.006

Quick mental math: To estimate kilojoules from calories, divide the number of calories by 239.

Conversion Examples

1 cal × 0.004184 =

0.004 kJ

1 Calories = 0.004 Kilojoules

5 cal × 0.004184 =

0.021 kJ

5 Calories = 0.021 Kilojoules

10 cal × 0.004184 =

0.042 kJ

10 Calories = 0.042 Kilojoules

25 cal × 0.004184 =

0.105 kJ

25 Calories = 0.105 Kilojoules

50 cal × 0.004184 =

0.209 kJ

50 Calories = 0.209 Kilojoules

100 cal × 0.004184 =

0.418 kJ

100 Calories = 0.418 Kilojoules

Calorie to Kilojoule Table

Quick convert your value:

cal =—kJ

Start:Step:Rows:Precision:

Calorie (cal)	Kilojoule (kJ)	Fraction
100	0.4184	27/64
200	0.8368	27/32
300	1.2552	1 1/4
400	1.6736	1 43/64
500	2.092	2 3/32
600	2.5104	2 33/64
700	2.9288	2 59/64
800	3.3472	3 11/32
900	3.7656	3 49/64
1,000	4.184	4 3/16
1,100	4.6024	4 39/64
1,200	5.0208	5 1/64
1,300	5.4392	5 7/16
1,400	5.8576	5 55/64
1,500	6.276	6 9/32
1,600	6.6944	6 11/16
1,700	7.1128	7 7/64
1,800	7.5312	7 17/32
1,900	7.9496	7 61/64
2,000	8.368	8 3/8

Unit Definitions

What is a Calorie (cal)?

Metric (SI)Worldwide

A calorie (cal) is a unit of energy defined as the amount of heat needed to raise the temperature of one gram of water by one degree Celsius.

History

The term 'calorie' was first introduced in the early 19th century by Nicolas Clément. It became a standard unit for measuring heat energy in the context of physics and chemistry.

Current Use

Today, calories are commonly used to quantify the energy content in food, as well as the energy expended during physical activities.

Learn more about Calorie

What is a Kilojoule (kJ)?

Metric (SI)Worldwide

A kilojoule (kJ) is a derived unit of energy in the International System of Units (SI), equivalent to 1000 joules.

History

The kilojoule was introduced in the late 19th century and became widely accepted as a standard measurement for energy, especially in scientific contexts.

Current Use

Kilojoules are now widely used in nutrition labeling, especially in countries that have adopted the metric system, allowing for clearer communication of energy content.

Learn more about Kilojoule

Frequently Asked Questions

How many kilojoules are in 500 calories?

To convert 500 calories to kilojoules, simply multiply by the conversion factor. 500 cal x 0.004184 kJ/cal equals 2.092 kJ. This conversion is useful when looking at the energy content of snacks; for instance, a chocolate bar may contain 500 calories, providing a quick reference for energy intake.

How does calorie intake affect workouts?

Understanding calories in kilojoules can help optimize your workouts. For example, if you burn 800 calories during a workout, that's approximately 3.347 kJ (800 cal x 0.004184 kJ/cal). Knowing this conversion can help you gauge how much energy you expend and how to adjust your diet accordingly to meet fitness goals.

Why is it important to convert calories to kilojoules in cooking?

In cooking, especially when following international recipes, energy measurements can differ. If a recipe calls for 200 calories, converting it to kilojoules (200 cal x 0.004184 kJ/cal = 0.837 kJ) helps in accurately measuring the energy content of dishes. This is crucial for dietary restrictions and nutritional planning.

How are calories converted to kilojoules in food labeling?

Food labels often present energy in both calories and kilojoules to cater to different regions. For instance, if a product states it contains 250 calories, that equals approximately 1.045 kJ (250 cal x 0.004184 kJ/cal). Understanding this helps consumers make informed choices based on their dietary needs.

What is the significance of converting energy units in fitness tracking?

Fitness apps may display energy burned in both calories and kilojoules. If you log a session that burns 600 calories, that's about 2.513 kJ (600 cal x 0.004184 kJ/cal). This dual measurement can help users better understand their energy balance and adjust their exercise and nutrition plans accordingly.

Popular Energy Conversions

Kilowatt to HorsepowerkW → HP Calorie to Kilocaloriecal → kcal Joule to CalorieJ → cal Kilowatt-hour to BTUkWh → BTU BTU to JouleBTU → J Kilocalorie to Joulekcal → J

Convert Calorie to Other Units

Calorie to Kilojoule→ kJ Calorie to Joule→ J Calorie to Watt-hour→ Wh Calorie to Kilowatt-hour→ kWh Calorie to BTU→ BTU Calorie to Kilowatt→ kW Calorie to Horsepower→ HP Calorie to Newton-Meter→ N·m

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Joule to KilojouleJ → kJ Joule to CalorieJ → cal Kilojoule to JoulekJ → J Kilojoule to CaloriekJ → cal Kilojoule to KilocaloriekJ → kcal