How Many Amps Is 3000 Watts?
3,000 W is 25.00 A at 120 V DC. At other common voltages — 240 V: 12.50 A. Use the calculator below for any voltage or circuit type.
3000 Watts to Amps — DC Reference Chart
| Voltage | Current (DC) | Application |
|---|---|---|
| 12 V | 250.0000 A | 12V automotive / RV / solar |
| 24 V | 125.0000 A | 24V solar / industrial DC |
| 48 V | 62.5000 A | 48V telecom / e-bike |
| 120 V | 25.0000 A | US household standard |
| 240 V | 12.5000 A | US/EU 240V circuit |
| 480 V | 6.2500 A | Industrial 3-phase (per phase) |
Breaker sizing: At 120V, 3000W draws 25A. Per NEC 210.20, size breakers at 125% of continuous load: 25 × 1.25 = 31.25A. This requires a 40A breaker. At 240V (12.5A × 1.25 = 15.63A), a 20A breaker is required. Note: 3000W at 120V is a heavy load — many electricians prefer 240V circuits for loads above 2400W. Always consult a licensed electrician.
In practice: a 3000 W inverter
At 120 V, 3,000 W means 25 A — beyond any standard household receptacle, which is why 3 kW loads are nearly always 240 V devices drawing 12.5 A. The number bites hardest on the DC side of an off-grid inverter: 3,000 W from a 12 V bank is roughly 250 A after conversion losses, demanding 4/0 cable and a class-T fuse. Many van builders switch to a 24 V or 48 V bank at exactly this power level purely to keep cable sizes sane.
Frequently Asked Questions
How many amps is 3000 watts at 120V?
3000 watts at 120V DC = 3000 ÷ 120 = 25.0000 amps. For AC single-phase with PF 0.8: 3000 ÷ (120 × 0.8) = 31.2500 amps.
How many amps is 3000 watts at 240V?
3000 watts at 240V DC = 3000 ÷ 240 = 12.5000 amps. For AC single-phase with PF 0.8: 3000 ÷ (240 × 0.8) = 15.6250 amps.
What size breaker do I need for 3000 watts?
At 120V, 3000W draws 25A. The NEC requires breakers sized at 125% for continuous loads: 25 × 1.25 = 31.25A. A 40A breaker is required. At 240V (12.5A), a 20A breaker is required.