500 watts to amps

500 watts is 4.17 amps at 120 volts and 2.08 amps at 240 volts, at a power factor of 1.

500 watts to amps at common voltages

500 watts in amps by voltage, power factor 1
VoltageAmps, A
12 V DC41.67
24 V DC20.83
120 V4.17
240 V2.08
208 V three phase1.39
480 V three phase0.6
0204060Amps, AVoltage12 V DC12 V DC, Amps: 41.6741.6724 V DC24 V DC, Amps: 20.8320.83120 V120 V, Amps: 4.174.17240 V240 V, Amps: 2.082.08208 V three phase208 V three phase, Amps: 1.391.39480 V three phase480 V three phase, Amps: 0.60.6
500 watts in amps by voltage.

The AC and three-phase rows assume a power factor of 1, as for heaters and incandescent lamps. Motors and electronics draw more current for the same watts.

How to convert 500 watts to amps

Amps = watts ÷ volts: 500 W ÷ 120 V = 4.17 A, and 500 W ÷ 240 V = 2.08 A. On three phase, amps = watts ÷ (1.732 × volts): 500 W ÷ (1.732 × 208 V) = 1.39 A per line. At a power factor of 0.8, 500 W at 120 V draws 5.21 A.

How much of a 15 or 20 amp circuit 500 watts uses

On a 120 V circuit, 500 W (4.17 A) uses 28% of a 15 amp circuit and 21% of a 20 amp circuit. A 500 W load that runs for three hours or more should stay within 80% of the circuit rating: 12 A on a 15 amp circuit and 16 A on a 20 amp circuit. At 4.17 A, a 500 W continuous load needs a 15 amp circuit.

Nearby values

Amps for 100 to 3,000 watts at 120 V and 240 V
Watts, W120 V, A240 V, A
1000.830.42
5004.172.08
1,0008.334.17
1,50012.56.25
2,00016.678.33
3,0002512.5

Watts to amps calculator

Convert
W
V
Phase

1 for heaters and lights; motors and electronics 0.8–0.95

Result
4.17 A
Power
500 W
Voltage
120 V
Share of a 15 A circuit at this voltage
28%

How it is calculated

  1. Amps = 500 ÷ (120) = 4.17