A kilocalorie (kcal) equals 1,000 small calories and is the unit behind the food "Calorie" shown on nutrition labels.
Kilocalories to Millijoules
Convert Kilocalorie (kcal) to Millijoule (mJ) instantly with an exact formula, conversion table, and FAQ.
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Convert kilocalories (kcal) to millijoules (mJ) instantly with formula, conversion table, and FAQ.
A millijoule (mJ) is a metric-prefixed unit of energy equal to 10-3 joules, a fraction of a single joule, using the SI milli prefix.
mJ = kcal × 4184000
Results update instantly for Kilocalories to Millijoules conversions.
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Formula
mJ = kcal × 4184000
kcal = mJ × 2.390057361e-07
Conversion table
| 1 kcal | 4.184000e+06 mJ |
| 5 kcal | 2.092000e+07 mJ |
| 10 kcal | 4.184000e+07 mJ |
| 20 kcal | 8.368000e+07 mJ |
| 50 kcal | 2.092000e+08 mJ |
| 100 kcal | 4.184000e+08 mJ |
| 500 kcal | 2.092000e+09 mJ |
| 1000 kcal | 4.184000e+09 mJ |
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How the formula works
Both kilocalorie and millijoule measure the same physical quantity, so converting between them is a single multiplication. Multiply a value in kilocalories by 4184000 to get millijoules. To reverse the conversion, multiply a millijoule value by 2.390057361e-07 to get back to kilocalories.
Frequently asked questions
What is Kilocalorie (kcal)?
A kilocalorie (kcal) equals 1,000 small calories and is the unit behind the food "Calorie" shown on nutrition labels.
What is Millijoule (mJ)?
A millijoule (mJ) is a metric-prefixed unit of energy equal to 10-3 joules, a fraction of a single joule, using the SI milli prefix.
How do I convert kilocalories to millijoules?
Multiply the kilocalorie value by 4184000 to get the equivalent in millijoules. For example, 5 kcal × 4184000 = 2.092000e+07 mJ.
Is this conversion exact?
Yes. Both units are defined against the SI base unit for this dimension, so the factor 4184000 is an exact, non-rounded value.
Can I convert millijoules back to kilocalories?
Yes. Divide the millijoule value by 4184000, or multiply it by 2.390057361e-07, to get kilocalories.
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About converting kilocalories to millijoules
A kilocalorie (kcal) equals 1,000 small calories and is the unit behind the food "Calorie" shown on nutrition labels. A millijoule (mJ) is a metric-prefixed unit of energy equal to 10-3 joules, a fraction of a single joule, using the SI milli prefix.
Use this calculator to move between kilocalories and millijoules accurately for homework, engineering, billing, or everyday energy calculations. The Universal Converter uses exact unit factors, so results stay consistent across the site.