Volts to Watts Calculator

Convert Volts to Watts with the formula, a worked example and a table of typical values. Working shown step by step.

Voltage 230 V, current 5 A gives

1,150 W

Estimate only. Not engineering or safety advice. Check the result against the applicable standard and the equipment data, and have a competent engineer review it before it is relied on. Terms of use.

Open in the calculator with these values

Formula

P = V × I R = V / I

Worked example

Input	Value
Voltage	230 V
Current	5 A

P = V × I = 230 × 5 = 1,150 W
R = V / I = 46 Ω

Typical values

Voltage (V)	Power (W)
12	60
24	120
110	550
230	1,150
400	2,000

Other inputs are the same as in the worked example above.

Assumptions

Steady DC or purely resistive AC load
AC values are RMS

For reactive loads include power factor (watts to amps).

Frequently asked questions

How do I convert Volts to Watts?

P = V × I; R = V / I. Worked example: Voltage 230 V, current 5 A gives 1,150 W.

What do I need to enter?

Enter voltage and current. Change the unit of a value with its selector and the result stays the same.

How accurate are the results?

Every figure comes from the same tested engine as the Elecmetric calculators and is meant for estimating. Check design values against the standard and the equipment data you work to.

Next steps in a design: Ohm's Law Volts to Amps Ohm's Law (V, I, R, P)
Opposite direction: Watts to Volts
Also see: Joules to Watts Watts to Joules Joules to Volts Volts to Joules
Formula guides: Ohm’s Law Formulas and Power Wheel AC Circuit Formulas: Reactance and Impedance
All 78 conversions Power from Voltage and Current in Elecmetric