Ohm's Law Calculator
Solve Ohm's law the complete way. Enter any two of voltage, current, resistance, and power, and WattSimple fills in the other two from the full power wheel — then shows the wire ampacity for the resulting current.
Enter any two values — WattSimple solves the other two.
Power
600 W
- Voltage
- 120 V
- Current
- 5 A
- Resistance
- 24 Ω
- Power
- 600 W
NEC wire & breaker for this load
- Breaker
- 15 A
- Min. copper wire (75°C)
- 14 AWG
Copper, 75°C terminations, NEC Table 310.16. Real installs may need derating for ambient heat, conduit fill, or voltage drop. Full wire & breaker chart. Always confirm with a licensed electrician + local AHJ.
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