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Convert Kilocalories to Kilojoules — Instantly

Convert kilocalories to kilojoules (kJ) instantly using the formula kilojoules = kilocalories × 4.184. Includes a calculator, conversion table, worked examples, and FAQs.

Kilocalories to kilojoules converter

Energy in kilocalories
Kilojoules → kJ
Enter a value above to see the result
Formula kilojoules = kilocalories × 4.184

Kilocalories to Kilojoules Conversion Table

Common kilocalorie to kilojoule conversions at a glance, using the exact relationship 1 kilocalorie = 4.184 kJ.

Common kilocalorie to kilojoule conversions from 0.1 kcal to 10,000 kcal
Kilocalories (kcal) Calculation Kilojoules (kJ)
0.1 kcal 0.1 × 4.184 0.4184 kJ
0.5 kcal 0.5 × 4.184 2.092 kJ
1 kcal 1 × 4.184 4.184 kJ
2 kcal 2 × 4.184 8.368 kJ
5 kcal 5 × 4.184 20.92 kJ
10 kcal 10 × 4.184 41.84 kJ
50 kcal 50 × 4.184 209.2 kJ
100 kcal 100 × 4.184 418.4 kJ
500 kcal 500 × 4.184 2,092 kJ
1,000 kcal 1,000 × 4.184 4,184 kJ
5,000 kcal 5,000 × 4.184 20,920 kJ
10,000 kcal 10,000 × 4.184 41,840 kJ

How to Convert Kilocalories to Kilojoules

Converting kilocalories to kilojoules is simple when you use the correct conversion factor.

The Formula

Kilocalories and kilojoules are both units of energy used in nutrition, chemistry, exercise science, and general energy measurement. This page uses the exact relationship 1 kilocalorie = 4.184 kilojoules.

kilojoules = kilocalories × 4.184

To convert kilojoules back to kilocalories, divide kilojoules by 4.184.

How to Turn Kilocalories into Kilojoules — Step by Step

1

Write down the kilocalorie value

Identify the number of kilocalories you want to convert — for example, 10 kcal.

2

Multiply by 4.184

10 kcal × 4.184 = 41.84 kilojoules. This gives you the equivalent energy in kilojoules.

3

Label your answer

Always write the unit (kJ or kilojoules) after the number so the result is clear and unambiguous.

What Is the Difference Between Kilocalories and Kilojoules?

Kilocalories and kilojoules are both units of energy. Kilojoules are part of the SI system, while kilocalories are commonly used in food energy labeling, diet planning, exercise tracking, and nutrition discussions.

The relationship used on this page is: 1 kilocalorie = 4.184 kilojoules. To convert kilocalories to kilojoules, multiply the number of kilocalories by 4.184.

For example, 0.5 kcal = 2.092 kJ, 1 kcal = 4.184 kJ, and 10 kcal = 41.84 kJ.

This conversion is useful in nutrition labels, food energy comparisons, workout tracking, chemistry calculations, and general energy conversions.

Sample Kilocalorie to Kilojoule Calculations

Here is how to calculate kilocalories to kilojoules for commonly searched values.

0.5 kilocalorie to kilojoules

0.5 × 4.184 = 2.092 kilojoules.

1 kilocalorie to kilojoules

1 × 4.184 = 4.184 kilojoules.

2 kilocalories to kilojoules

2 × 4.184 = 8.368 kilojoules.

5 kilocalories to kilojoules

5 × 4.184 = 20.92 kilojoules.

10 kilocalories to kilojoules

10 × 4.184 = 41.84 kilojoules.

50 kilocalories to kilojoules

50 × 4.184 = 209.2 kilojoules.

100 kilocalories to kilojoules

100 × 4.184 = 418.4 kilojoules.

1,000 kilocalories to kilojoules

1,000 × 4.184 = 4,184 kilojoules.


Frequently Asked Questions

Everything you need to know about converting kilocalories to kilojoules.