A kilocalorie (kcal) equals 1,000 small calories and is the unit behind the food "Calorie" shown on nutrition labels.
Kilocalories to Petajoules
Convert Kilocalorie (kcal) to Petajoule (PJ) instantly with an exact formula, conversion table, and FAQ.
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Convert kilocalories (kcal) to petajoules (PJ) instantly with formula, conversion table, and FAQ.
Context values
Some unit families need one extra value for a physically accurate result.
A petajoule (PJ) is a metric-prefixed unit of energy equal to 1015 joules, using the SI peta prefix.
PJ = kcal × 4.184000000e-12
Results update instantly for Kilocalories to Petajoules conversions.
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Formula
PJ = kcal × 4.184000000e-12
kcal = PJ × 239005736138
Conversion table
| 1 kcal | 4.184000e-12 PJ |
| 5 kcal | 2.092000e-11 PJ |
| 10 kcal | 4.184000e-11 PJ |
| 20 kcal | 8.368000e-11 PJ |
| 50 kcal | 2.092000e-10 PJ |
| 100 kcal | 4.184000e-10 PJ |
| 500 kcal | 2.092000e-09 PJ |
| 1000 kcal | 4.184000e-09 PJ |
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How the formula works
Both kilocalorie and petajoule measure the same physical quantity, so converting between them is a single multiplication. Multiply a value in kilocalories by 4.184000000e-12 to get petajoules. To reverse the conversion, multiply a petajoule value by 239005736138 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 Petajoule (PJ)?
A petajoule (PJ) is a metric-prefixed unit of energy equal to 1015 joules, using the SI peta prefix.
How do I convert kilocalories to petajoules?
Multiply the kilocalorie value by 4.184000000e-12 to get the equivalent in petajoules. For example, 5 kcal × 4.184000000e-12 = 2.092000e-11 PJ.
Is this conversion exact?
Yes. Both units are defined against the SI base unit for this dimension, so the factor 4.184000000e-12 is an exact, non-rounded value.
Can I convert petajoules back to kilocalories?
Yes. Divide the petajoule value by 4.184000000e-12, or multiply it by 239005736138, to get kilocalories.
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About converting kilocalories to petajoules
A kilocalorie (kcal) equals 1,000 small calories and is the unit behind the food "Calorie" shown on nutrition labels. A petajoule (PJ) is a metric-prefixed unit of energy equal to 1015 joules, using the SI peta prefix.
Use this calculator to move between kilocalories and petajoules accurately for homework, engineering, billing, or everyday energy calculations. The Universal Converter uses exact unit factors, so results stay consistent across the site.