Watts to Volts Calculator
Convert Watts to Volts with the formula, a worked example and a table of typical values. Working shown step by step.
Try your own numbers
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
Worked example
| Input | Value |
|---|---|
| Real power | 1,150 W |
| Line current | 5 A |
| Power factor | 1 |
| Current type | Single-phase AC |
| Voltage type (three-phase only) | Line-to-line (L-L) |
- V = P / (1 × I × PF) = 1,150 / (1 × 5 × 1) = 230 V
Typical values
| Real power (W) | Line voltage (V) |
|---|---|
| 100 | 20 |
| 500 | 100 |
| 1,150 | 230 |
| 2,000 | 400 |
| 5,000 | 1,000 |
Other inputs are the same as in the worked example above.
Assumptions
- Balanced load
- Voltage is line-to-line for three-phase unless line-to-neutral is chosen
- Current is the line current
- AC values are RMS
For DC the power factor is taken as 1. If you know resistance, use the watts, volts, amps, ohms solver. Engineering mode adds the line-to-line or line-to-neutral choice for three-phase.
Frequently asked questions
How do I convert Watts to Volts?
P = k × V × I × PF; k = √3 (three-phase L-L), 3 (three-phase L-N) or 1 (single-phase, DC; PF = 1 for DC). Worked example: Real power 1,150 W, line current 5 A, power factor 1, current type Single-phase AC gives 230 V.
What do I need to enter?
Enter real power, voltage, line current, power factor and current type. Leave blank the value you want to find, and the form solves for it. Change the unit of a value with its selector and the result stays the same.
Does single-phase or three-phase change the answer?
Yes. Pick the circuit type that matches the supply. Three-phase uses √3 with the line-to-line voltage, single-phase uses the voltage as it is, and DC, where it is offered, takes the power factor as 1. The formula above shows each case.
Which power factor should I use?
Read it from the equipment nameplate or data sheet. Typical values are only a guide: about 1.0 for a resistive load and about 0.85 for a fully loaded induction motor. Do not use typical values for accurate work.
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.
Related
Next steps in a design: kW to AmpsAmps to kWOhm's Law (V, I, R, P)
Opposite direction: Volts to Watts
Also see: Joules to Watts Watts to Joules Joules to Volts Volts to Joules
Formula guides: Ohm’s Law Formulas and Power WheelThree-Phase Power FormulasPower Factor and the Power Triangle
All 78 conversionsPower, Voltage, Current with Power Factor (solve any) in Elecmetric