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.
Calories to Exajoules
Convert Calorie (cal) to Exajoule (EJ) instantly with an exact formula, conversion table, and FAQ.
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Convert calories (cal) to exajoules (EJ) instantly with formula, conversion table, and FAQ.
Context values
Some unit families need one extra value for a physically accurate result.
A exajoule (EJ) is a metric-prefixed unit of energy equal to 1018 joules, using the SI exa prefix.
EJ = cal × 4.184000000e-18
Results update instantly for Calories to Exajoules conversions.
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Formula
EJ = cal × 4.184000000e-18
cal = EJ × 2.390057361e+17
Conversion table
| 1 cal | 4.184000e-18 EJ |
| 5 cal | 2.092000e-17 EJ |
| 10 cal | 4.184000e-17 EJ |
| 20 cal | 8.368000e-17 EJ |
| 50 cal | 2.092000e-16 EJ |
| 100 cal | 4.184000e-16 EJ |
| 500 cal | 2.092000e-15 EJ |
| 1000 cal | 4.184000e-15 EJ |
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How the formula works
Both calorie and exajoule measure the same physical quantity, so converting between them is a single multiplication. Multiply a value in calories by 4.184000000e-18 to get exajoules. To reverse the conversion, multiply a exajoule value by 2.390057361e+17 to get back to calories.
Frequently asked questions
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.
What is Exajoule (EJ)?
A exajoule (EJ) is a metric-prefixed unit of energy equal to 1018 joules, using the SI exa prefix.
How do I convert calories to exajoules?
Multiply the calorie value by 4.184000000e-18 to get the equivalent in exajoules. For example, 5 cal × 4.184000000e-18 = 2.092000e-17 EJ.
Is this conversion exact?
Yes. Both units are defined against the SI base unit for this dimension, so the factor 4.184000000e-18 is an exact, non-rounded value.
Can I convert exajoules back to calories?
Yes. Divide the exajoule value by 4.184000000e-18, or multiply it by 2.390057361e+17, to get calories.
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About converting calories to exajoules
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. A exajoule (EJ) is a metric-prefixed unit of energy equal to 1018 joules, using the SI exa prefix.
Use this calculator to move between calories and exajoules accurately for homework, engineering, billing, or everyday energy calculations. The Universal Converter uses exact unit factors, so results stay consistent across the site.