How Many Watts Is 15 Amps?

Answer
1,800 W at 120 V · 3,600 W at 240 V

Watts = amps × volts. 15 A at 120 V = 1,800 W and 15 A at 240 V = 3,600 W. A 15 A breaker should carry at most 80% of that for continuous loads: 1,440 W at 120 V.

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1.0 for heaters and lights; 0.8–0.9 for motors.
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    For estimating and educational purposes only. Results are approximate and are not a substitute for a licensed professional, the manufacturer's instructions or your local code. Disclaimer

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    15 amps in watts by voltage

    VoltageWattsContinuous (80%)
    12 V180 W144 W
    120 V1,800 W1,440 W
    208 V3,120 W2,496 W
    240 V3,600 W2,880 W
    480 V 3-phase12,471 W9,977 W

    For motors and electronics, multiply by the power factor (typically 0.8–0.95) to get real watts.

    Frequently asked questions

    How many watts can a 15 amp breaker handle?

    1,800 W at 120 V or 3,600 W at 240 V, and 80% of that for continuous loads.

    How many watts is 15 amps at 12 volts?

    180 W.

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