Watts to Joules
Power converter

Watts to Volts Calculator

Calculate voltage in volts from power in watts and the current in amps.

W
A

How Watts to Volts works

Voltage, current, and power are linked by the power equation P = V × I. Rearranging for voltage gives V = P ÷ I, so dividing power in watts by current in amps yields the voltage in volts.

This is handy when a device's power draw and current are known but its operating voltage is not. It applies directly to DC and resistive AC loads where the power factor is 1.

Formula
1V = P(W) ÷ I(A)

Rearranged from P = V × I (valid for DC and resistive AC loads).

Watts to Volts conversion table

Reference Table5 rows
Voltage from power and current (DC / resistive loads).
Power↕At 1 A↕At 10 A↕
12 W
12 V
1.2 V
120 W
120 V
12 V
600 W
600 V
60 V
1,200 W
1,200 V
120 V
2,400 W
2,400 V
240 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 the power in watts by the current in amps. Volts = Watts ÷ Amps. For example, 1,200 W ÷ 10 A = 120 V.

Can you find volts from watts alone?

No. You also need the current in amps (or the resistance). Watts measure power, which is the product of voltage and current, so one more quantity is required.

Does this work for AC circuits?

It works directly for DC and resistive AC loads. For reactive AC loads you must also divide by the power factor: V = P ÷ (I × PF).

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