How to use Watts to Amps
Enter the power, voltage and power factor and the result appears straight away. Everything runs in your browser, so nothing you type is uploaded.
The formula
amps = watts ÷ (volts × power factor)
Examples
- 1200 W at 120 V
10 A Assumes single-phase AC with the power factor entered (use 1 for DC).
- 2400 W at 240 V
10 A Assumes single-phase AC with the power factor entered (use 1 for DC).
- 750 W motor at 230 V, power factor 0.85
3.83631714 A Assumes single-phase AC with the power factor entered (use 1 for DC).
Limitations and assumptions
Single-phase formula. Three-phase circuits use an extra √3 factor. Always follow electrical codes and a qualified electrician for installations.
Frequently asked questions
What is the formula?
Amps = watts ÷ (volts × power factor).
Why does the power factor matter?
For AC loads such as motors, apparent power exceeds real power, so the same watts draw more current.
Does it cover three phase?
No, it assumes single phase AC or DC.
Is this safe for sizing a breaker?
It is an estimate. Follow local electrical codes and ask an electrician.