Watts to Amps Calculator

At nominal 230V single-phase with a power factor of 1.0 (typical for resistive heaters or kettles), 2400 watts draws exactly 10.43 Amps. This calculation uses the single-phase formula: Current = Power ÷ Voltage. Since a standard Australian power outlet is rated for 10 Amps, a 2400W device runs right at the physical thermal limit of the socket.

Divide total wattage by nominal 230V. For example, a 3,600W built-in oven draws 3,600 ÷ 230 = 15.65 Amps. A 7,200W four-zone induction cooktop running at full boost draws 7,200 ÷ 230 = 31.3 Amps, requiring a dedicated 32A or 40A radial sub-circuit with minimum 6mm² twin-and-earth cable.

You should use 230V for single-phase calculations and 400V for three-phase. Although many Australian sparkies still refer to 240V and 415V, the official nominal voltage standards in Australia were changed to 230V and 400V in 2000 to align with international standards. Using 230V is also safer because it results in a slightly higher calculated current draw, preventing cable under-sizing.

Power factor is a ratio between the real working power (Watts) and the apparent power (Volt-Amps) flowing in an AC circuit. For purely resistive loads like heaters and incandescent lighting, the power factor is 1.0. For inductive loads with windings or magnetic fields (motors, compressors, fans, pumps), the power factor drops to around 0.80 to 0.90, which increases the actual current drawn for the same wattage.

At nominal 230V single-phase, a standard 10 Amp power point can support a maximum continuous load of 2,300 Watts (2.3 kW) assuming a power factor of 1.0. Running appliances that exceed this rating continuously on a single circuit will trigger the thermal element of your circuit breaker to protect the cable from thermal damage.

The current draw of a split system depends on its rated electrical input (not its cooling output capacity). A typical 2.5 kW cooling capacity unit draws about 800 Watts of electrical power, which equates to roughly 3.5 Amps at 230V. A larger 7 kW ducted or split system might draw 2,600 Watts of electrical power, resulting in about 11.3 Amps, requiring a dedicated circuit.

Watts (W) measures real power that performs actual work. Volt-Amps (VA) and kiloVolt-Amps (kVA) measure apparent power, which is the product of voltage and current. In DC and resistive AC circuits, Watts and VA are identical. In inductive AC circuits (motors), apparent power is higher than real power. Apparent power (VA) is used to size electrical infrastructure like cables and transformers.

A typical built-in domestic electric oven has a connected load rating of 3,600 Watts (3.6 kW). At 230V single-phase, this draws 15.65 Amps. Consequently, standard ovens cannot be plugged into standard 10A GPOs. They require a dedicated radial circuit wired back to the switchboard, protected by a 20A circuit breaker, and terminated at a 15A socket or hardwired isolator.

Technically yes, but it is right on the line. A 2400W appliance draws 10.43 Amps. Standard Australian power outlets (GPOs) are rated for 10 Amps continuous. While GPOs can handle a slight temporary overload, plugging multiple high-draw devices into the same double GPO will overload the socket and trip the sub-circuit circuit breaker.

In Australia, 15A appliances (such as heavy-duty compressors, workshop welders, and commercial coffee machines) feature an enlarged vertical earth pin. This physical keying ensures high-current appliances cannot be plugged into standard 10A socket-outlets, protecting 10A household wiring from persistent overheating.

Under AS/NZS 3000 Appendix C, domestic power circuits protected by a 16A or 20A circuit breaker do not have a hard legal cap on the number of double GPO points because diversity assumes not all points will draw peak current simultaneously. However, high-draw appliances over 10A continuous must be installed on dedicated individual sub-circuits.

A standard Level 2 single-phase residential EV charger is rated at 7.2 kW (7,200 Watts) and draws exactly 31.3 Amps. This heavy continuous current draw requires a dedicated sub-circuit wired with minimum 6 mm² TPS cable, protected by a 40A RCBO, and connected via a dedicated wall box charger.

No. This calculator computes the steady-state running current based on nominal inputs. Electric motors and compressors experience a starting current surge (inrush current) that can be 5 to 7 times higher than their running current for a fraction of a second. This inrush must be considered separately when choosing circuit breaker trip curves (e.g., selecting Type C or D breakers).

Exceeding the current capacity of a circuit causes the conductors to heat up. If the current draw is slightly above the rating (e.g., 22A on a 20A breaker), the thermal overload strip in the circuit breaker will heat up and trip after a few minutes. If a short circuit occurs, drawing hundreds of amps, the magnetic trip element activates instantly to disconnect the supply and prevent a fire.

To convert Amps to Watts, swap the calculation direction. The formulas are: Watts = Amps × Volts (for DC), Watts = Amps × Volts × Power Factor (for single-phase AC), and Watts = Amps × Volts × √3 × Power Factor (for three-phase AC). Multiply the current draw by the nominal voltage and the power factor of the load.