A ronnajoule (RJ) is a metric-prefixed unit of energy equal to 1027 joules, using the SI ronna prefix.
Ronnajoules to Calories
Convert Ronnajoule (RJ) to Calorie (cal) instantly with an exact formula, conversion table, and FAQ.
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Convert ronnajoules (RJ) 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 = RJ × 2.390057361e+26
Results update instantly for Ronnajoules to Calories conversions.
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Formula
cal = RJ × 2.390057361e+26
RJ = cal × 4.184000000e-27
Conversion table
| 1 RJ | 2.390057e+26 cal |
| 5 RJ | 1.195029e+27 cal |
| 10 RJ | 2.390057e+27 cal |
| 20 RJ | 4.780115e+27 cal |
| 50 RJ | 1.195029e+28 cal |
| 100 RJ | 2.390057e+28 cal |
| 500 RJ | 1.195029e+29 cal |
| 1000 RJ | 2.390057e+29 cal |
Related conversions
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How the formula works
Both ronnajoule and calorie measure the same physical quantity, so converting between them is a single multiplication. Multiply a value in ronnajoules by 2.390057361e+26 to get calories. To reverse the conversion, multiply a calorie value by 4.184000000e-27 to get back to ronnajoules.
Frequently asked questions
What is Ronnajoule (RJ)?
A ronnajoule (RJ) is a metric-prefixed unit of energy equal to 1027 joules, using the SI ronna 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 ronnajoules to calories?
Multiply the ronnajoule value by 2.390057361e+26 to get the equivalent in calories. For example, 5 RJ × 2.390057361e+26 = 1.195029e+27 cal.
Is this conversion exact?
Yes. Both units are defined against the SI base unit for this dimension, so the factor 2.390057361e+26 is an exact, non-rounded value.
Can I convert calories back to ronnajoules?
Yes. Divide the calorie value by 2.390057361e+26, or multiply it by 4.184000000e-27, to get ronnajoules.
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About converting ronnajoules to calories
A ronnajoule (RJ) is a metric-prefixed unit of energy equal to 1027 joules, using the SI ronna 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 ronnajoules 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.