About this calculator
Enter any two of voltage, current, resistance and power to get the other two. Handy for checking appliance loads on a circuit.
How it’s calculated
V = I × R, and P = V × I. For AC loads with a power factor below 1, real current will be higher.
Worked example
With these inputs:
- Volts (V)
- 230
- Amps (A)
- 0
- Resistance (Ω)
- 0
- Power (W)
- 1500
the result is:
- Current
- 6.52 A
- Voltage
- 230 V
- Current
- 6.522 A
- Resistance
- 35.267 Ω
- Power
- 1,500 W (1.5 kW)
Tips from the trade
- A standard 10 A power point on 230 V supplies about 2.3 kW, which is why most portable heaters top out at 2.4 kW.
Results are estimates for planning and pricing. Check quantities against your drawings, the manufacturer’s data and the NCC and Australian Standards before ordering.