# How to convert volts to electron-volts

How to convert electrical voltage in volts (V) to energy in electron-volts (eV).

You can calculate electron-volts from volts and elementary charge or coulombs, but you can't convert volts to electron-volts since volt and electron-volt units represent different quantities.

### Volts to eV calculation with elementary charge

The energy *E* in electron-volts (eV) is equal to the voltage
*V* in volts (V), times the
electric charge *Q* in
elementary charge or proton/electron charge (e):

*E*_{(eV)} = *V*_{(V)}* *×* Q*_{(e)}

The elementary charge is the electric charge of 1 electron with the e symbol.

So

electronvolt = volt × elementary charge

or

eV = V × e

#### Example

What is the energy in electron-volts that is consumed in an electrical circuit with voltage supply of 20 volts and charge flow of 40 electron charges?

*E* = 20V × 40e = 800eV

### Volts to eV calculation with coulombs

The energy E in electron-volts (eV) is equal to the voltage V in volts (V), times
the electrical charge Q in coulombs (C) divided by 1.602176565×10^{-19}:

*E*_{(eV)} = *V*_{(V)}* *×* Q*_{(C)}
/ 1.602176565×10^{-19}

So

electronvolt = volt × coulomb / 1.602176565×10^{-19}

or

eV = V × C / 1.602176565×10^{-19}

#### Example

What is the energy in electron-volts that is consumed in an electrical circuit with voltage supply of 20 volts and charge flow of 2 coulombs?

*E* = 20V × 2C / 1.602176565×10^{-19} =
2.4966×10^{20}eV