Watts to Joules
Power converter

Watts to Volts Calculator

Find voltage from power in watts and current in amps.

W
A
  • DC
  • AC — single phase
  • AC — three phase

How Watts to Volts works

Volts measure electric potential. For a DC circuit, voltage = power ÷ current (V = P ÷ I).

This calculator helps you determine the necessary voltage rating for a power supply or wiring system.

Formula
1V = P ÷ I (DC)DC
2V = P ÷ (I × PF) (AC 1-phase)

PF is Power Factor.

Watts to Volts conversion table

Reference Table4 rows
Watts to volts at common current values (DC).
Power↕At 5 A↕At 10 A↕At 20 A↕
100 W
20 V
10 V
5 V
500 W
100 V
50 V
25 V
1000 W
200 V
100 V
50 V
1500 W
300 V
150 V
75 V
💡 Click any row to auto-fill the calculator aboveClick column headers to sort

FAQ: Watts to Volts

How do you convert watts to volts?

Divide power in watts by current in amps: volts = watts ÷ amps.

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