Calculators

Watts to Amps Calculator

Convert watts to amps for DC, single-phase AC and three-phase AC circuits, with power factor.

W
V
UK/EU mains: 230 V. US/Canada: 120 V.
1 for resistive loads like heaters; 0.8–0.95 for motors.

Enter your values and press Calculate.

How to use the Watts to Amps calculator

Use this to check whether an appliance will overload a circuit or fuse. A UK 13 A plug fuse allows up to about 3,000 W at 230 V.

Formula

DC: I = P ÷ V. Single-phase AC: I = P ÷ (V × PF). Three-phase AC: I = P ÷ (√3 × VL-L × PF).

Frequently asked questions

How many amps is 1500 watts?

About 6.5 A at 230 V (UK), or 12.5 A at 120 V (US).

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