A kilocalorie (kcal) equals 1,000 small calories and is the unit behind the food "Calorie" shown on nutrition labels.
Kilocalories to Quectojoules
Convert Kilocalorie (kcal) to Quectojoule (qJ) instantly with an exact formula, conversion table, and FAQ.
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Convert kilocalories (kcal) to quectojoules (qJ) instantly with formula, conversion table, and FAQ.
Context values
Some unit families need one extra value for a physically accurate result.
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.
qJ = kcal × 4.184000000e+33
Results update instantly for Kilocalories to Quectojoules conversions.
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Formula
qJ = kcal × 4.184000000e+33
kcal = qJ × 2.390057361e-34
Conversion table
| 1 kcal | 4.184000e+33 qJ |
| 5 kcal | 2.092000e+34 qJ |
| 10 kcal | 4.184000e+34 qJ |
| 20 kcal | 8.368000e+34 qJ |
| 50 kcal | 2.092000e+35 qJ |
| 100 kcal | 4.184000e+35 qJ |
| 500 kcal | 2.092000e+36 qJ |
| 1000 kcal | 4.184000e+36 qJ |
Related conversions
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How the formula works
Both kilocalorie and quectojoule measure the same physical quantity, so converting between them is a single multiplication. Multiply a value in kilocalories by 4.184000000e+33 to get quectojoules. To reverse the conversion, multiply a quectojoule value by 2.390057361e-34 to get back to kilocalories.
Frequently asked questions
What is Kilocalorie (kcal)?
A kilocalorie (kcal) equals 1,000 small calories and is the unit behind the food "Calorie" shown on nutrition labels.
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.
How do I convert kilocalories to quectojoules?
Multiply the kilocalorie value by 4.184000000e+33 to get the equivalent in quectojoules. For example, 5 kcal × 4.184000000e+33 = 2.092000e+34 qJ.
Is this conversion exact?
Yes. Both units are defined against the SI base unit for this dimension, so the factor 4.184000000e+33 is an exact, non-rounded value.
Can I convert quectojoules back to kilocalories?
Yes. Divide the quectojoule value by 4.184000000e+33, or multiply it by 2.390057361e-34, to get kilocalories.
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About converting kilocalories to quectojoules
A kilocalorie (kcal) equals 1,000 small calories and is the unit behind the food "Calorie" shown on nutrition labels. 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.
Use this calculator to move between kilocalories and quectojoules accurately for homework, engineering, billing, or everyday energy calculations. The Universal Converter uses exact unit factors, so results stay consistent across the site.