Joules to electronvolts
Type a value in joules to see it in electronvolts straight away, or type in the second box to convert back.
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Processing and privacy: The result is calculated inside your browser and your data is not sent to any server.
How to use it
- Type the value in the joules box.
- Read the result in electronvolts as you type, and pick the precision you need.
- Swap the direction to convert back, or copy the result.
How it is calculated
eV = J × 6.241509074e+18
Multiply the value in joules by 6.241509074e+18 to get electronvolts.
Example
To convert 25 J to electronvolts: 25 × 6.241509074e+18 = 1.56038e+20 eV.
Conversion table
| Joules (J) | Electronvolts (eV) |
|---|---|
| 1 | 6.24151e+18 |
| 2 | 1.2483e+19 |
| 3 | 1.87245e+19 |
| 5 | 3.12075e+19 |
| 10 | 6.24151e+19 |
| 20 | 1.2483e+20 |
| 25 | 1.56038e+20 |
| 50 | 3.12075e+20 |
| 100 | 6.24151e+20 |
| 250 | 1.56038e+21 |
| 500 | 3.12075e+21 |
| 1,000 | 6.24151e+21 |
About the units
- Joule
- The SI unit of energy, equal to the work done by a force of one newton moving an object one meter.
- Electronvolt
- The energy an electron gains crossing a potential difference of one volt, exactly 1.602176634 × 10⁻¹⁹ joules since the 2019 SI definition.
Limits and caveats
- Results are rounded for display and computed with the browser's floating point precision (about 15 significant digits).
- Both unit factors are exact by their official definitions.
Questions about this tool
How many electronvolts are in one joule?
1 J = 6.24151e+18 eV exactly.
How do I convert joules to electronvolts?
Use eV = J × 6.241509074e+18. For example, 25 J = 1.56038e+20 eV.
How many joules are in one electronvolt?
1 eV = 1.60218e-19 J.
Which calorie do these converters use?
The thermochemical calorie, exactly 4.184 joules, the factor many countries use to turn kcal into kJ on food labels. The International Table calorie is 4.1868 joules, less than 0.07% larger.
What is the difference between kW and kWh?
A kilowatt is a unit of power, the rate of using energy, while a kilowatt-hour is an amount of energy. A 2 kW heater running for three hours uses 6 kWh.