How Many Amps Is 800 Watts?
At 120 V DC, 800 watts = 6.6667 A. At 240 V DC, 800 watts = 3.3333 A. For AC circuits, divide by voltage × power factor (e.g. at 120V AC, PF 0.8: 8.3333 A). Use the calculator below for any voltage or circuit type.
Real example: an 800 W microwave oven
"800 W" is the classic microwave query — but that figure is cooking (output) power, not what the oven pulls from the wall. As a plain resistive 800 W load (say a heater element) the current at 120 V is 6.67 A and at 240 V is 3.33 A.
800 Watts to Amps — DC Reference Chart
| Voltage | Current (DC) | Application |
|---|---|---|
| 12 V | 66.6667 A | 12V automotive / RV / solar |
| 24 V | 33.3333 A | 24V solar / industrial DC |
| 48 V | 16.6667 A | 48V telecom / e-bike |
| 120 V | 6.6667 A | US household standard |
| 240 V | 3.3333 A | US/EU 240V circuit |
| 480 V | 1.6667 A | Industrial 3-phase (per phase) |
Wire & breaker: As a resistive 800 W load at 120 V the current is 6.67 A, so 6.67 × 1.25 = 8.33 A and a 15 A breaker covers it. A real 800 W microwave draws more — often ~1,200 W input — so give it a dedicated 20 A circuit in practice. Always verify with an electrician. For the full method see watts vs amps.
Frequently Asked Questions
How many amps is 800 watts at 120V?
800 watts at 120V DC = 800 ÷ 120 = 6.6667 amps. For AC single-phase with PF 0.8: 800 ÷ (120 × 0.8) = 8.3333 amps.
How many amps is 800 watts at 240V?
800 watts at 240V DC = 800 ÷ 240 = 3.3333 amps. For AC single-phase with PF 0.8: 800 ÷ (240 × 0.8) = 4.1667 amps.
Why does an 800 W microwave draw more than 6.67 A?
A microwave's "800 W" is its cooking output. The magnetron and transformer are only ~60–70% efficient, so the input is closer to 1,200 W — about 10 A at 120 V, not 6.67 A. For pure resistive loads (heaters, incandescent bulbs) input and output watts are equal. Check the appliance nameplate for its true input rating.