Convert watts to amps at any voltage (120 V, 240 V, 12 V). Instant answer with formula and circuit-breaker guidance.
| Input | Result |
|---|---|
| 1500 W at 120 V | 12.5 A |
| 1500 W at 240 V | 6.25 A |
| 1500 W at 12 V | 125 A |
Divide watts by volts: A = W / V. At 120 V, 1500 W draws 12.5 A; at 240 V the same heater draws only 6.25 A because the voltage is doubled.
The same power at higher voltage needs less current. US outlets are 120 V (15–20 A circuits); US dryers, ovens and EU outlets are 230–240 V.
For AC loads with motors or electronics, real amps = watts ÷ (volts × PF). A 1500 W motor at PF 0.8 on 120 V draws 1500 ÷ 96 = 15.6 A, not 12.5 A.