Electrical Power Calculator
Calculate electrical power using P=VI, P=I²R, or P=V²/R. Supports all combinations of voltage, current, and resistance.
How It Works
Calculate electrical power using P=VI, P=I²R, or P=V²/R. Supports all combinations of voltage, current, and resistance. Enter your values above and click Calculate to get instant results.
Formula
P = V × I | P = I² × R | P = V² / R
Quick Examples
- 120V × 2A = 240W
- 5A through 10Ω: P = 25 × 10 = 250W
- 240V²/60Ω = 960W
Frequently Asked Questions
What is electrical power?
Electrical power (P) measured in watts (W) is the rate at which electrical energy is transferred. It equals voltage multiplied by current: P = V × I.
How do I calculate energy cost?
Multiply watts by hours to get watt-hours, then divide by 1000 for kilowatt-hours (kWh). Multiply kWh by your electricity rate to find cost.