1 calorie equals approximately 0.0042 kilojoules (kJ).
This conversion is based on the fact that 1 calorie (cal), a unit used to measure energy in food, is equivalent to 4.184 joules. Since 1 kilojoule (kJ) is 1,000 joules, dividing 4.184 by 1,000 gives the approximate value of 0.0042 kJ per calorie.
Energy Conversion from Calories to Kilojoules
Converting calories to kJ involves understanding the relationship between these two units. Since 1 cal equals 4.184 joules, and 1 kJ equals 1,000 joules, the calculation involves dividing 4.184 by 1,000. This results in the factor 0.004184, which is used to convert any calorie value into kilojoules. For example, 10 calories would be 10 x 0.004184 = 0.04184 kJ.
Conversion Tool
Result in kj:
Conversion Formula
The formula for converting calories to kilojoules is: kj = cal × 0.004184. This formula works because 1 calorie equals 4.184 joules, and 1 kilojoule equals 1,000 joules. By multiplying the calorie value by 0.004184, you get the equivalent energy in kilojoules.
For example, if you want to convert 5 calories, multiply 5 by 0.004184, which equals 0.02092 kJ.
Conversion Example
– Converting 2 calories:
– Step 1: Take the calorie value, which is 2.
– Step 2: Multiply 2 by 0.004184.
– Step 3: 2 × 0.004184 = 0.008368.
– Result: 2 calories is approximately 0.0084 kJ.
– Convert 10 calories:
– Step 1: Take the value, 10.
– Step 2: Multiply 10 by 0.004184.
– Step 3: 10 × 0.004184 = 0.04184.
– Result: 10 calories equals 0.0418 kJ.
– Convert 0.5 calories:
– Step 1: Take 0.5.
– Step 2: Multiply 0.5 by 0.004184.
– Step 3: 0.5 × 0.004184 = 0.002092.
– Result: 0.5 calories is approximately 0.0021 kJ.
– Convert 15 calories:
– Step 1: Take 15.
– Step 2: Multiply 15 by 0.004184.
– Step 3: 15 × 0.004184 = 0.06276.
– Result: 15 calories is around 0.0628 kJ.
– Convert 100 calories:
– Step 1: Take 100.
– Step 2: Multiply 100 by 0.004184.
– Step 3: 100 × 0.004184 = 0.4184.
– Result: 100 calories equals 0.4184 kJ.
Conversion Chart
| Calories | Kilojoules (kJ) |
|---|---|
| -24.0 | -0.1004 |
| -20.0 | -0.0837 |
| -15.0 | -0.0628 |
| -10.0 | -0.0418 |
| -5.0 | -0.0209 |
| 0.0 | 0.0000 |
| 5.0 | 0.0209 |
| 10.0 | 0.0418 |
| 15.0 | 0.0628 |
| 20.0 | 0.0837 |
| 25.0 | 0.1046 |
| 26.0 | 0.1084 |
This chart shows calorie values from -24.0 to 26.0 and their corresponding kilojoule values. You can find the energy in kJ by locating your calorie number in the first column and reading across to see the conversion result.
Related Conversion Questions
- How many kilojoules are in 1 calorie of energy?
- What is the kj equivalent of 1 calorie food energy?
- Convert 1 calorie to kilojoules for nutritional labeling?
- How do I calculate kilojoules from calories in recipes?
- What is the energy conversion factor from calorie to kJ?
- How many kilojoules is 1 calorie of exercise energy?
- Can I convert 1 calorie to kj for scientific calculations?
Conversion Definitions
Calorie: A calorie is a unit of energy that measures the amount of heat needed to raise the temperature of 1 gram of water by 1°C. It is commonly used in nutrition to quantify the energy content in food.
Kilojoule: A kilojoule (kJ) is a metric unit of energy equal to 1,000 joules, used to express energy in scientific, nutritional, and physical contexts, representing the work done or heat transferred in energy calculations.
Conversion FAQs
How accurate is the conversion from calorie to kilojoules?
The conversion factor of 0.004184 is precise for scientific purposes, based on the exact relationship between calories and joules. Minor differences may occur depending on rounding but are typically insignificant in practical applications.
Why is the conversion from calorie to kJ important in nutrition?
Many countries and food labels use kilojoules to measure energy content, making it essential to convert calories into kJ for accurate nutrition information, dietary planning, and understanding energy consumption.
Can this conversion be used for both small and large energy values?
Yes, the formula applies universally, whether converting small quantities like 0.5 calories or larger amounts like 1,000 calories, providing consistent and accurate results across different energy levels.
Is there a difference between calorie and kilocalorie in this conversion?
In food energy contexts, the calorie often refers to a kilocalorie (kcal), which equals 1,000 small calories. The conversion factor remains the same, but it’s important to distinguish between the two when precise measurements are required.
Are there any tools to quickly convert calories to kilojoules?
Yes, online calculators, mobile apps, and the provided JavaScript tool allow quick and accurate conversion, saving time and reducing errors in manual calculations.