A microjoule (uJ) is a metric-prefixed unit of energy equal to 10-6 joules, a fraction of a single joule, using the SI micro prefix.
Microjoules to Calories
Convert Microjoule (uJ) to Calorie (cal) instantly with an exact formula, conversion table, and FAQ.
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Convert microjoules (uJ) 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 = uJ × 2.390057361e-07
Results update instantly for Microjoules to Calories conversions.
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Formula
cal = uJ × 2.390057361e-07
uJ = cal × 4184000
Conversion table
| 1 uJ | 2.390057e-07 cal |
| 5 uJ | 0.000001 cal |
| 10 uJ | 0.000002 cal |
| 20 uJ | 0.000005 cal |
| 50 uJ | 0.000012 cal |
| 100 uJ | 0.000024 cal |
| 500 uJ | 0.000120 cal |
| 1000 uJ | 0.000239 cal |
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How the formula works
Both microjoule and calorie measure the same physical quantity, so converting between them is a single multiplication. Multiply a value in microjoules by 2.390057361e-07 to get calories. To reverse the conversion, multiply a calorie value by 4184000 to get back to microjoules.
Frequently asked questions
What is Microjoule (uJ)?
A microjoule (uJ) is a metric-prefixed unit of energy equal to 10-6 joules, a fraction of a single joule, using the SI micro 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 microjoules to calories?
Multiply the microjoule value by 2.390057361e-07 to get the equivalent in calories. For example, 5 uJ × 2.390057361e-07 = 0.000001 cal.
Is this conversion exact?
Yes. Both units are defined against the SI base unit for this dimension, so the factor 2.390057361e-07 is an exact, non-rounded value.
Can I convert calories back to microjoules?
Yes. Divide the calorie value by 2.390057361e-07, or multiply it by 4184000, to get microjoules.
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About converting microjoules to calories
A microjoule (uJ) is a metric-prefixed unit of energy equal to 10-6 joules, a fraction of a single joule, using the SI micro 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 microjoules 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.