Milliamp-hours to Watt-hours calculation formula

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

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

Watt-hours = Milliamp-hours * Volts / 1000

or

Wh = mAh * V / 1000