I = P / VNo power factor needed for DC circuits.
Reverse Conversion Tool
Amps to Watts Calculator
Convert amps to watts for any DC or AC circuit. Enter current in amps, circuit voltage, select your system type, and add power factor for AC loads. The result is real power in watts.
Conversion direction
Quick voltage presets
Power factor varies by load. Use the equipment value when available.
Calculated result1000 W · 120 V · DC
8.333 A
Formula used
I = P / VCustom voltage is always supported.
Formulas Used
I = P / (V × PF)Single-phase AC — multiply voltage by power factor.
I = P / (√3 × V × PF)Three-phase AC — divide by √3 ≈ 1.732.
Amps to Watts Formula
For DC circuits: P = V × I. For single-phase AC: P = V × I × PF. For three-phase AC: P = √3 × V × I × PF. Power factor (PF) is between 0 and 1 — use the nameplate value or 0.8–0.9 for most inductive loads.
When to Use Amps to Watts
Use this tool when you know the current draw from a breaker reading, clamp meter, or equipment spec and want to find the power consumption in watts or kilowatts. It is the reverse of the main Watts to Amps Calculator.
Frequently Asked Questions
How do I convert 10 amps to watts at 120V?
For a DC or resistive AC circuit: P = 120 × 10 = 1,200 W. For an AC load with PF 0.9: P = 120 × 10 × 0.9 = 1,080 W.
How do I convert 15 amps to watts at 240V?
DC / resistive: P = 240 × 15 = 3,600 W. AC with PF 0.85: P = 240 × 15 × 0.85 = 3,060 W.
Is watts = amps × volts always correct?
For DC and purely resistive AC loads, yes. For reactive AC loads you must multiply by the power factor: W = A × V × PF.
What power factor should I use?
Check the equipment nameplate. Motors are typically 0.7–0.9, LED drivers 0.85–0.95, resistive heaters 1.0. If unknown, use 0.8 as a conservative estimate.