Ohms to Watts Calculator
Selecting correct resistor wattage rating (1/4W, 1/2W, 1W, 5W, 10W) without burnout. Calculates power dissipation in heat for resistors and heating elements.
Step-by-Step Derivation ▼ Show Steps
Calculations adhere to standard electrical equations and National Electrical Code guidelines.
Engineering Principles & Calculations
This calculator uses the exact mathematical relationships between Resistance (Ω), Current (A) or Voltage (V) to determine Power (Watts), Resistor Heat Loss (BTU/hr). In practical applications, electrical systems must account for safety derating factors, nominal vs actual voltages, and conductor resistance losses.
Calculates power dissipation in heat for resistors and heating elements.
Typical Application & Best Practices
Selecting correct resistor wattage rating (1/4W, 1/2W, 1W, 5W, 10W) without burnout.
Ohms to Watts Calculator Benchmark Lookup Table
| Resistance | Applied Volts | Power (Watts) | Current | Package Size |
|---|---|---|---|---|
| 10 Ohms | 12V DC | 14.40 W | 1.20 A | 25W Aluminum Chassis |
| 50 Ohms | 12V DC | 2.88 W | 0.24 A | 5W Ceramic Wirewound |
| 100 Ohms | 12V DC | 1.44 W | 0.12 A | 3W or 5W Power Resistor |
| 220 Ohms | 5V DC | 0.11 W | 22.7 mA | 1/4 W (0.25W) Resistor |
| 1,000 Ohms | 12V DC | 0.14 W | 12.0 mA | 1/4 W Carbon Film |