A petajoule (PJ) is a metric-prefixed unit of energy equal to 1015 joules, using the SI peta prefix.
Petajoules to Calories
Convert Petajoule (PJ) to Calorie (cal) instantly with an exact formula, conversion table, and FAQ.
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Convert petajoules (PJ) to calories (cal) instantly with formula, conversion table, and FAQ.
Context values
Some unit families need one extra value for a physically accurate result.
A (small) calorie is a thermochemical unit of heat energy equal to 4.184 joules, historically the energy needed to raise 1 gram of water by 1°C.
cal = PJ × 239005736137667
Results update instantly for Petajoules to Calories conversions.
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Formula
cal = PJ × 239005736137667
PJ = cal × 4.184000000e-15
Conversion table
| 1 PJ | 2.390057e+14 cal |
| 5 PJ | 1.195029e+15 cal |
| 10 PJ | 2.390057e+15 cal |
| 20 PJ | 4.780115e+15 cal |
| 50 PJ | 1.195029e+16 cal |
| 100 PJ | 2.390057e+16 cal |
| 500 PJ | 1.195029e+17 cal |
| 1000 PJ | 2.390057e+17 cal |
Related conversions
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How the formula works
Both petajoule and calorie measure the same physical quantity, so converting between them is a single multiplication. Multiply a value in petajoules by 239005736137667 to get calories. To reverse the conversion, multiply a calorie value by 4.184000000e-15 to get back to petajoules.
Frequently asked questions
What is Petajoule (PJ)?
A petajoule (PJ) is a metric-prefixed unit of energy equal to 1015 joules, using the SI peta prefix.
What is Calorie (cal)?
A (small) calorie is a thermochemical unit of heat energy equal to 4.184 joules, historically the energy needed to raise 1 gram of water by 1°C.
How do I convert petajoules to calories?
Multiply the petajoule value by 239005736137667 to get the equivalent in calories. For example, 5 PJ × 239005736137667 = 1.195029e+15 cal.
Is this conversion exact?
Yes. Both units are defined against the SI base unit for this dimension, so the factor 239005736137667 is an exact, non-rounded value.
Can I convert calories back to petajoules?
Yes. Divide the calorie value by 239005736137667, or multiply it by 4.184000000e-15, to get petajoules.
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About converting petajoules to calories
A petajoule (PJ) is a metric-prefixed unit of energy equal to 1015 joules, using the SI peta prefix. A (small) calorie is a thermochemical unit of heat energy equal to 4.184 joules, historically the energy needed to raise 1 gram of water by 1°C.
Use this calculator to move between petajoules and calories accurately for homework, engineering, billing, or everyday energy calculations. The Universal Converter uses exact unit factors, so results stay consistent across the site.