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 Kilocalories
Convert Quectojoule (qJ) to Kilocalorie (kcal) instantly with an exact formula, conversion table, and FAQ.
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Convert quectojoules (qJ) to kilocalories (kcal) instantly with formula, conversion table, and FAQ.
Context values
Some unit families need one extra value for a physically accurate result.
A kilocalorie (kcal) equals 1,000 small calories and is the unit behind the food "Calorie" shown on nutrition labels.
kcal = qJ × 2.390057361e-34
Results update instantly for Quectojoules to Kilocalories conversions.
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Formula
kcal = qJ × 2.390057361e-34
qJ = kcal × 4.184000000e+33
Conversion table
| 1 qJ | 2.390057e-34 kcal |
| 5 qJ | 1.195029e-33 kcal |
| 10 qJ | 2.390057e-33 kcal |
| 20 qJ | 4.780115e-33 kcal |
| 50 qJ | 1.195029e-32 kcal |
| 100 qJ | 2.390057e-32 kcal |
| 500 qJ | 1.195029e-31 kcal |
| 1000 qJ | 2.390057e-31 kcal |
Related conversions
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How the formula works
Both quectojoule and kilocalorie measure the same physical quantity, so converting between them is a single multiplication. Multiply a value in quectojoules by 2.390057361e-34 to get kilocalories. To reverse the conversion, multiply a kilocalorie value by 4.184000000e+33 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 Kilocalorie (kcal)?
A kilocalorie (kcal) equals 1,000 small calories and is the unit behind the food "Calorie" shown on nutrition labels.
How do I convert quectojoules to kilocalories?
Multiply the quectojoule value by 2.390057361e-34 to get the equivalent in kilocalories. For example, 5 qJ × 2.390057361e-34 = 1.195029e-33 kcal.
Is this conversion exact?
Yes. Both units are defined against the SI base unit for this dimension, so the factor 2.390057361e-34 is an exact, non-rounded value.
Can I convert kilocalories back to quectojoules?
Yes. Divide the kilocalorie value by 2.390057361e-34, or multiply it by 4.184000000e+33, to get quectojoules.
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About converting quectojoules to kilocalories
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 kilocalorie (kcal) equals 1,000 small calories and is the unit behind the food "Calorie" shown on nutrition labels.
Use this calculator to move between quectojoules and kilocalories accurately for homework, engineering, billing, or everyday energy calculations. The Universal Converter uses exact unit factors, so results stay consistent across the site.