kW to hp converter, kilowatts to horsepower.

To convert kW to hp, multiply the kilowatts by 1.341022. So 1 kW is 1.341022 hp, 10 kW is 13.4102 hp and 100 kW is 134.1 hp. That answer is for mechanical horsepower, the "hp" of US and UK car and engine listings. Two other horsepowers are in use, so the converter shows them under the result: metric horsepower (1.359622 PS per kW) and electric horsepower (1.340483 per kW).

How to use the converter

1. Type the power in the Kilowatts (kW) box. A car rated at 110 kW gives 147.51 hp.
2. Read the big result for mechanical horsepower, then the cards under it for Metric horsepower (PS, also written cv or CV), Electric horsepower and Watts. If your spec sheet says PS, take the metric card.
3. Choose Decimals. 0 or 1 is plenty for an engine, 4 helps when you compare with another calculator.
4. Click a row in Common values to load it, press Copy result or Copy link to share the number, or Print chart for a sheet to keep.
5. Press the swap button (or the S key) to go from horsepower back to kilowatts.

Three horsepowers, three exact factors

Horsepower is not one unit. The converter keeps each one exact and rounds only the last digit shown.

NIST Special Publication 811, Appendix B.8 (checked 26 Oct 2026) lists electric horsepower as 746 W and marks it exact. It prints mechanical horsepower as 745.6999 W and metric horsepower as 735.4988 W, rounded. This page goes one step further. With the exact foot (0.3048 m), pound (0.45359237 kg) and standard gravity (9.80665 m/s2), 550 ft·lbf/s works out to 745.69987158227022 W, and 75 kgf·m/s to 735.49875 W. NIST also lists boiler, UK and water horsepower, which are rare and are not used here.

Which one is on your spec sheet

US and UK listings give mechanical horsepower, often written hp or bhp (brake horsepower, measured at the engine). Many European spec sheets show kW and PS side by side. A metric horsepower is about 1.4 percent smaller than a mechanical one: 100 PS is 98.632 hp. Electric horsepower is a round 746 W, only 0.04 percent above the mechanical one, and appears on some motor nameplates. When a source only says "hp", assume mechanical unless it is clearly European.

Worked examples

• A 110 kW car engine. 110 × 1.341022 = 147.51 hp, or 149.56 PS in metric horsepower.
• A 150 kW engine. 201.15 hp mechanical, 203.94 PS.
• A 22 kW industrial motor. 29.5 hp mechanical, 29.49 hp in electric horsepower.
• A 0.75 kW small motor. 1.0058 hp, so it is just over 1 hp.
• A 3 kW generator. 4.023 hp.

A shortcut and how far off it is

Multiply by 1.34, which is the same as adding a third and a bit. For 100 kW that gives 134 hp against the exact 134.1, which is only 0.08 percent low. Multiplying by 4/3 (1.3333) is quicker still but 0.57 percent low: 100 kW becomes 133.3 hp.

Power at the engine is not power at the wheels

An engine rating describes the output at the engine. The power that reaches the road is lower because of the gearbox and driveline. That is a measuring question, not a unit question, so this converter does not adjust for it. It only changes the unit.

Smaller and larger powers

The same factor works at every scale. A 500 W blender motor is 0.671 hp. A 1 MW generator, which is 1,000 kW, is 1,341 hp. Because 1 kW is 1,000 W, you can also type watts divided by 1,000 into the kW box. For 1,500 W type 1.5.

How many digits to trust

Engine ratings are usually whole numbers, so 134 hp for a 100 kW engine says all there is to say. The long factor is for people who compare two calculators or who work with the exact definition. If your answer differs from another site in the third decimal, check the factor first: many sites use 1.341, 1.34102 or 1.3410220896 and all are the same number rounded differently.

Common sizes

These are examples of the factor, not a list of real products.

For the other direction see the HP to kW converter. To size a cable or a breaker from watts, use the watts to amps calculator. For any other unit try the unit converter.