A quectojoule (qJ) is a metric-prefixed unit of energy equal to 10-30 joules, a fraction of a single joule, using the SI quecto prefix.
Quectojoules to Calories
Convert Quectojoule (qJ) to Calorie (cal) instantly with an exact formula, conversion table, and FAQ.
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Convert quectojoules (qJ) 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 = qJ × 2.390057361e-31
Results update instantly for Quectojoules to Calories conversions.
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Formula
cal = qJ × 2.390057361e-31
qJ = cal × 4.184000000e+30
Conversion table
| 1 qJ | 2.390057e-31 cal |
| 5 qJ | 1.195029e-30 cal |
| 10 qJ | 2.390057e-30 cal |
| 20 qJ | 4.780115e-30 cal |
| 50 qJ | 1.195029e-29 cal |
| 100 qJ | 2.390057e-29 cal |
| 500 qJ | 1.195029e-28 cal |
| 1000 qJ | 2.390057e-28 cal |
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How the formula works
Both quectojoule and calorie measure the same physical quantity, so converting between them is a single multiplication. Multiply a value in quectojoules by 2.390057361e-31 to get calories. To reverse the conversion, multiply a calorie value by 4.184000000e+30 to get back to quectojoules.
Frequently asked questions
What is Quectojoule (qJ)?
A quectojoule (qJ) is a metric-prefixed unit of energy equal to 10-30 joules, a fraction of a single joule, using the SI quecto 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 quectojoules to calories?
Multiply the quectojoule value by 2.390057361e-31 to get the equivalent in calories. For example, 5 qJ × 2.390057361e-31 = 1.195029e-30 cal.
Is this conversion exact?
Yes. Both units are defined against the SI base unit for this dimension, so the factor 2.390057361e-31 is an exact, non-rounded value.
Can I convert calories back to quectojoules?
Yes. Divide the calorie value by 2.390057361e-31, or multiply it by 4.184000000e+30, to get quectojoules.
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About converting quectojoules to calories
A quectojoule (qJ) is a metric-prefixed unit of energy equal to 10-30 joules, a fraction of a single joule, using the SI quecto 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 quectojoules 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.