Watts to Amps
Convert between watts, amps, and volts for AC and DC circuits. Handles single-phase and three-phase AC with power factor — useful for electrical load planning and wiring.
12.5000 A
How to use the watts to amps
Enter power, voltage, and (for AC) the power factor.
Formula & explanation
I = P / (V × PF). For DC or purely resistive AC, PF = 1.
Examples
1500 W at 120 V → 12.5 A.
Frequently asked questions
- How do I convert watts to amps?
- Divide watts by volts: I = P / V. For AC circuits with reactive loads, also divide by the power factor: I = P / (V × PF).
- What power factor should I use?
- Use 1.0 for DC circuits and purely resistive AC loads (heaters, incandescent bulbs). Use 0.8–0.95 for motors, transformers, and switching power supplies.
- Why does a higher power factor mean lower current for the same watts?
- A poor power factor means the current and voltage are out of phase, so more current must flow to deliver the same real power. Improving power factor reduces wasted current.
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