Electrical Power Calculator
P = IV — compute power from voltage and current, or from voltage and resistance, or current and resistance.
Result
Power
24.0000 W
0.0240 kW.
- FormulaP = V × I = 12 × 2
- Watts24.0000
- kW0.0240
- kWh per hr0.0240
Step-by-step
- P = V × I = 12 × 2 = 24.0000 W.
How to use this calculator
- Pick which two of V/I/R you have.
- Enter both values.
- Read power in watts and kW.
About this calculator
Power in an electrical circuit is the rate of energy transfer. P = IV in DC; for AC with phase difference φ, P = IV cos φ (real power). Energy used over time: E = P × t (kWh = kW × hours). A 100 W bulb running for 10 hours uses 1 kWh.
Frequently asked
In DC and resistive AC, watts = VA. In AC with reactive load, real power (W) = VA × power factor (cos φ).
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