# How to convert mAh to Wh

How to convert milliamp-hours (mAh) to watt-hours (Wh).

### milliamp-hours to watt-hours calculation

The energy *E*_{(Wh)} in watt-hours is equal to the electric charge *Q*_{(mAh) }in milliamp-hours times the
voltage * V*_{(V) }in volts (V) divided by 1000:

*E*_{(Wh)} = *Q*_{(mAh)} × *V*_{(V)}* */* *1000

So watt-hours is equal to milliamp-hours times volts divided by 1000:

watt-hours = milliamp-hours × volts / 1000

or

Wh = mAh × V / 1000

#### Example

Find the energy in watt-hours when the electric charge is 300 milliamp-hours and the voltage is 5 volts.

The energy *E* is equal to 300 milliamp-hours times 5 volts divided by 1000:

*E* = 300mAh × 5V / 1000 = 1.5Wh