How Many Amps Is 1500 Watts?
1,500 W is 12.50 A at 120 V DC. At other common voltages — 240 V: 6.25 A. Use the calculator below for any voltage or circuit type.
1500 Watts to Amps — DC Reference Chart
| Voltage | Current (DC) | Application |
|---|---|---|
| 12 V | 125.0000 A | 12V automotive / RV / solar |
| 24 V | 62.5000 A | 24V solar / industrial DC |
| 48 V | 31.2500 A | 48V telecom / e-bike |
| 120 V | 12.5000 A | US household standard |
| 240 V | 6.2500 A | US/EU 240V circuit |
| 480 V | 3.1250 A | Industrial 3-phase (per phase) |
Breaker sizing: At 120V, 1500W draws 12.5A. Per NEC 210.20, size breakers at 125% of continuous load: 12.5 × 1.25 = 15.63A. This requires a 20A breaker. Note: 1500W space heaters typically require a dedicated 20A circuit at 120V. At 240V (6.25A × 1.25 = 7.81A), a 15A breaker is sufficient. Always consult a licensed electrician.
In practice: the 1500 W ceiling on portable heaters
Portable electric heaters stop at 1,500 W because that is the most a 120 V plug-in appliance can safely draw: 12.5 A, or 83% of a 15 A breaker. A heater runs for hours, making it a continuous load, and the 80% rule caps a 15 A circuit at 12 A — so a 1,500 W heater genuinely belongs on a 20 A circuit. Running two from one circuit is the single most common cause of winter breaker trips.
Frequently Asked Questions
How many amps is 1500 watts at 120V?
1500 watts at 120V DC = 1500 ÷ 120 = 12.5000 amps. For AC single-phase with PF 0.8: 1500 ÷ (120 × 0.8) = 15.6250 amps.
How many amps is 1500 watts at 240V?
1500 watts at 240V DC = 1500 ÷ 240 = 6.2500 amps. For AC single-phase with PF 0.8: 1500 ÷ (240 × 0.8) = 7.8125 amps.
What size breaker do I need for 1500 watts?
At 120V, 1500W draws 12.5A. The NEC requires breakers sized at 125% for continuous loads: 12.5 × 1.25 = 15.63A. A 20A breaker is required. (1500W heaters need a dedicated 20A circuit). At 240V (6.25A), a 15A breaker is adequate.