Power Calculator
Calculate electrical power from voltage, current, or resistance
Power Calculator
Calculate electrical power (watts) using voltage and current (P = V × I), voltage and resistance (P = V² / R), or current and resistance (P = I² × R). Enter any two values to compute power and the remaining quantity.
⚡ Electrical Values
📊 Calculation Results
📋 Common Appliance Power Ratings
| Appliance | Power (W) | Current @ 120V (A) | Current @ 240V (A) |
|---|---|---|---|
| 💡 LED Light Bulb | 10 | 0.08 | 0.04 |
| 📺 Television (55") | 120 | 1.00 | 0.50 |
| 💻 Laptop Computer | 65 | 0.54 | 0.27 |
| 🍳 Toaster | 1,200 | 10.00 | 5.00 |
| 🔥 Space Heater | 1,500 | 12.50 | 6.25 |
| ❄️ Refrigerator | 150 | 1.25 | 0.63 |
| 👕 Clothes Dryer | 5,000 | 41.67 | 20.83 |
| 🌀 Central A/C | 3,500 | 29.17 | 14.58 |
| ⚡ Electric Oven | 2,500 | 20.83 | 10.42 |
| 🔌 Hair Dryer | 1,800 | 15.00 | 7.50 |
📚 Understanding Electrical Power
What is Electrical Power?
Electrical power is the rate at which electrical energy is transferred by an electric circuit, measured in watts (W). One watt equals one joule of energy per second, or one volt times one ampere.
Power Formulas
Electrical power can be calculated using P = V × I (watts = volts × amps), P = V² / R (using voltage and resistance), or P = I² × R (using current and resistance).
Practical Applications
Understanding power is essential for sizing circuit breakers, calculating electricity costs, selecting wire gauges, and ensuring electrical safety in homes and industrial settings.
Power Calculation Formulas
Electrical power represents the amount of work done per unit time by an electrical circuit. It is directly related to voltage, current, and resistance through several fundamental equations derived from Ohm's Law.
Three Key Power Equations
Power equals voltage times current
Power equals voltage squared divided by resistance
Power equals current squared times resistance
Power Unit Conversions
Kilowatt to watt
Horsepower to watt
Watt to BTU per hour
Megawatt to watt