# How to convert watts to volts

How to convert electric power in watts (W) to electrical voltage in volts (V).

You can calculate volts from watts and amps, but you can't convert watts to volts since watts and volts units do not measure the same quantity.

### DC watts to volts calculation formula

The voltage *V* in volts is equal to the power *P* in watts, divided by
the current *I* in amps:

*V*_{(V)} = *P*_{(W)}* */*
I*_{(A)}

So volts are equal to watts divided by amps.

volt = watt / amp

or

V = W / A

#### Example

What is the voltage in volts when the power consumption is 45 watts and the current flow is 3 amps?

*V* = 45W / 3A = 15V

### AC single phase watts to volts calculation formula

The RMS voltage *V* in volts is equal to the power *P* in
watts, divided by the
power factor *PF* times the phase current *I* in amps:

*V*_{(V)} = * P*_{(W)} / (*PF* × * I*_{(A)}* *
)

So volts are equal to watts divided by power factor times amps.

volts = watts / (*PF* × amps)

or

V = W / (*PF* × A)

#### Example

What is the RMS voltage in volts when the power consumption is 330 watts, the power factor is 0.8 and the phase current is 3.75 amps?

*V* = 330W / (0.8 × 3.75A) = 110V

### AC three phase watts to volts calculation formula

The line to line RMS voltage *V*_{L-L} in volts is equal to the power
*P* in
watts, divided by square root of 3 times the
power factor *PF* times the
phase current I in amps:

*V*_{L-L(V)} = * P*_{(W)} / (*√*3
× * PF* × * I*_{(A)}* *)

So volts are equal to watts divided by square root of 3 times power factor times amps.

volts = watts / (*√*3
× * PF* × amps)

or

V = W / (*√*3
× * PF* × A)

#### Example

What is the RMS voltage in volts when the power consumption is 330 watts, the power factor is 0.8 and the phase current flow is 2.165 amps?

*V* = 330W / (*√*3
× 0.8 × 2.165A) = 110V

How to convert volts to watts ►