Power converter

Horsepower to Watts Calculator

Convert mechanical, electric, or metric horsepower into watts and kilowatts.

How HP to Watts works

One horsepower is a fixed amount of power, so converting to watts is a simple multiplication. Mechanical horsepower equals 745.699872 watts, which is why a 1 hp motor is often labelled as roughly 746 W.

To size wiring, generators, or inverters for a motor rated in horsepower, convert to watts (or kilowatts) first. Choose the horsepower standard that matches the equipment's origin to keep the result accurate.

Formula

1W = hp × 745.699872 (mechanical)

2W = hp × 746 (electric)

3W = hp × 735.49875 (metric / PS)

1 mechanical hp = 745.7 W; 1 electric hp = 746 W; 1 metric hp = 735.5 W.

HP to Watts conversion table

Reference Table7 rows

Common horsepower values converted to watts (mechanical hp).
Horsepower↕	Watts↕	Kilowatts↕
0.5 hp	373 W	0.373 kW
1 hp	746 W	0.746 kW
2 hp	1,491 W	1.491 kW
5 hp	3,728 W	3.728 kW
10 hp	7,457 W	7.457 kW
25 hp	18,642 W	18.64 kW
100 hp	74,570 W	74.57 kW

💡 Click any row to auto-fill the calculator aboveClick column headers to sort

FAQ: HP to Watts

How do you convert horsepower to watts?

Multiply the horsepower by 745.7 for mechanical horsepower. For example, 5 hp × 745.7 = 3,728 W (about 3.73 kW).

Is 1 hp exactly 746 watts?

Mechanical horsepower is 745.699872 W, which rounds to 746 W. Electric horsepower is defined as exactly 746 W, so the two are effectively identical for everyday use.

How many watts is a 2 hp motor?

A 2 hp motor delivers about 1,491 watts of mechanical output (2 × 745.7). Its electrical input will be higher because motors are not 100% efficient.

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