How to Convert Watt-hours to Electronvolts (Wh to eV)
Energy conversions link food labels in kJ and kcal, SP Group bills in kWh and air-conditioner capacity in BTU. This guide shows how to convert watt-hours into electronvolts by hand, with examples and a quick-reference table.
The conversion
To convert watt-hours to electronvolts, multiply the value by 2.246943e+22. To go the other way, divide by the same number (or multiply by 4.450491e-23). For a quick estimate, multiply by about 22,000,000,000,000,000,000,000.
Electronvolts = watt-hours × 2.246943e+22
Worked examples
- 3 Wh = 6.740830e+22 eV
- 12.5 Wh = 2.808679e+23 eV
- 75 Wh = 1.685207e+24 eV
Watt-hours to Electronvolts table
| Watt-hours | Electronvolts |
|---|---|
| 1 Wh | 2.246943e+22 eV |
| 2 Wh | 4.493887e+22 eV |
| 5 Wh | 1.123472e+23 eV |
| 10 Wh | 2.246943e+23 eV |
| 20 Wh | 4.493887e+23 eV |
| 25 Wh | 5.617358e+23 eV |
| 50 Wh | 1.123472e+24 eV |
| 100 Wh | 2.246943e+24 eV |
| 250 Wh | 5.617358e+24 eV |
| 500 Wh | 1.123472e+25 eV |
| 1,000 Wh | 2.246943e+25 eV |
Common questions
Is Wh to eV exact?
The factors used here are the internationally defined values where they exist; results are rounded for display only.
How do I convert back?
Use the Electronvolts to Watt-hours converter.
Mistakes to avoid
Dropping the units
A bare number without a unit is easy to misread later. Always write the unit with the result.
Forgetting squared and cubed units
Area and volume factors are the length factor squared or cubed, so 1 m² is about 10.76 sq ft, not 3.28.
Multiplying when you should divide
Converting to a smaller unit gives a bigger number, and converting to a larger unit gives a smaller one. If your answer moves the wrong way, you have inverted the factor.
Background
A conversion table is handy for common values, but a calculator is faster and avoids interpolation errors for anything in between.
Unit conversion is simply multiplication by a fixed ratio. The ratio between two units of the same quantity never changes, so once you know it you can convert any value in either direction.
Writing the units next to every number while you work is the simplest way to avoid mistakes. If the units do not cancel to leave the one you want, the calculation is set up wrongly.
For any value, use the Watt-hours to Electronvolts Converter or browse all energy converters.
Run your own numbers: Watt-hours to Electronvolts Converter