Power converter

Watts to Horsepower Calculator

Convert electrical power in watts to mechanical, electric, or metric horsepower.

How Watts to HP works

Horsepower measures mechanical power, while watts measure electrical or general power. Because one mechanical horsepower equals 745.699872 watts, you convert watts to horsepower by dividing by that factor.

Motors and appliances are often rated in watts, but engines and pumps are commonly quoted in horsepower. Pick the horsepower standard that matches your context — mechanical (imperial), electric, or metric (PS) — since each uses a slightly different conversion factor.

Formula

1hp = W ÷ 745.699872 (mechanical)

2hp = W ÷ 746 (electric)

3hp = W ÷ 735.49875 (metric / PS)

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

Watts to HP conversion table

Reference Table7 rows

Common watt values converted to mechanical horsepower.
Watts↕	Mechanical hp↕	Metric hp (PS)↕
100 W	0.134 hp	0.136 PS
250 W	0.335 hp	0.340 PS
500 W	0.670 hp	0.680 PS
746 W	1.00 hp	1.014 PS
1,000 W	1.341 hp	1.360 PS
1,500 W	2.012 hp	2.039 PS
3,000 W	4.023 hp	4.079 PS

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

FAQ: Watts to HP

How many watts are in 1 horsepower?

One mechanical horsepower equals 745.699872 watts (often rounded to 746 W). Electric horsepower is defined as exactly 746 W, and metric horsepower (PS) is 735.49875 W.

How do you convert watts to horsepower?

Divide the power in watts by the horsepower factor. For mechanical horsepower, divide by 745.7. For example, 1,000 W ÷ 745.7 = 1.34 hp.

Which horsepower standard should I use?

Use mechanical horsepower for engines and US equipment, electric horsepower for electric motor ratings, and metric horsepower (PS) for European vehicle specifications.

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