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 Hectojoules
Convert Calorie (cal) to Hectojoule (hJ) instantly with an exact formula, conversion table, and FAQ.
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Convert calories (cal) to hectojoules (hJ) instantly with formula, conversion table, and FAQ.
Context values
Some unit families need one extra value for a physically accurate result.
A hectojoule (hJ) is a metric-prefixed unit of energy equal to 102 joules, using the SI hecto prefix.
hJ = cal × 0.04184
Results update instantly for Calories to Hectojoules conversions.
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Formula
hJ = cal × 0.04184
cal = hJ × 23.90057361
Conversion table
| 1 cal | 0.041840 hJ |
| 5 cal | 0.209200 hJ |
| 10 cal | 0.418400 hJ |
| 20 cal | 0.836800 hJ |
| 50 cal | 2.092000 hJ |
| 100 cal | 4.184000 hJ |
| 500 cal | 20.920000 hJ |
| 1000 cal | 41.840000 hJ |
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How the formula works
Both calorie and hectojoule measure the same physical quantity, so converting between them is a single multiplication. Multiply a value in calories by 0.04184 to get hectojoules. To reverse the conversion, multiply a hectojoule value by 23.90057361 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 Hectojoule (hJ)?
A hectojoule (hJ) is a metric-prefixed unit of energy equal to 102 joules, using the SI hecto prefix.
How do I convert calories to hectojoules?
Multiply the calorie value by 0.04184 to get the equivalent in hectojoules. For example, 5 cal × 0.04184 = 0.209200 hJ.
Is this conversion exact?
Yes. Both units are defined against the SI base unit for this dimension, so the factor 0.04184 is an exact, non-rounded value.
Can I convert hectojoules back to calories?
Yes. Divide the hectojoule value by 0.04184, or multiply it by 23.90057361, to get calories.
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About converting calories to hectojoules
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 hectojoule (hJ) is a metric-prefixed unit of energy equal to 102 joules, using the SI hecto prefix.
Use this calculator to move between calories and hectojoules accurately for homework, engineering, billing, or everyday energy calculations. The Universal Converter uses exact unit factors, so results stay consistent across the site.