kW to HP Calculator
Convert kilowatts to horsepower instantly — mechanical, metric and electric.
Convert kilowatts to horsepower instantly. The calculator shows both mechanical horsepower (the US/UK standard) and metric horsepower (PS), so it works for any spec sheet.
kW to HP Formula
How to Use This Calculator
- Enter the power in kilowatts.
- Read horsepower in both mechanical HP and metric PS.
Common Conversions
| Kilowatts | Mechanical HP | Metric PS |
|---|---|---|
| 50 | 67.1 | 68.0 |
| 100 | 134.1 | 136.0 |
| 150 | 201.2 | 203.9 |
| 200 | 268.2 | 271.9 |
Small kW Figures Are Almost Always Motor Sizes
If you arrived here converting something like 0.37 kW, 0.75 kW, 1.1 kW or 2.2 kW, you are almost certainly reading an electric motor nameplate, not a vehicle. Those apparently random numbers are the IEC standard motor sizes used across Europe and Asia — and they line up remarkably neatly with the NEMA horsepower sizes used in North America.
| IEC size (kW) | Exact HP | Nearest NEMA size |
|---|---|---|
| 0.18 | 0.24 | 1/4 hp |
| 0.25 | 0.34 | 1/3 hp |
| 0.37 | 0.50 | 1/2 hp |
| 0.55 | 0.74 | 3/4 hp |
| 0.75 | 1.01 | 1 hp |
| 1.1 | 1.48 | 1.5 hp |
| 1.5 | 2.01 | 2 hp |
| 2.2 | 2.95 | 3 hp |
| 4.0 | 5.36 | 5 hp |
| 5.5 | 7.38 | 7.5 hp |
| 7.5 | 10.06 | 10 hp |
| 11 | 14.75 | 15 hp |
| 15 | 20.12 | 20 hp |
| 18.5 | 24.81 | 25 hp |
| 22 | 29.50 | 30 hp |
| 30 | 40.23 | 40 hp |
| 37 | 49.62 | 50 hp |
| 45 | 60.35 | 60 hp |
| 55 | 73.76 | 75 hp |
| 75 | 100.58 | 100 hp |
The sizes look arbitrary because they follow a preferred number series — a roughly geometric progression where each step is about 30–40% larger than the last. That is why the ladder runs 0.55, 0.75, 1.1, 1.5, 2.2 rather than in round increments. The same logic sets NEMA's ½, ¾, 1, 1½, 2, 3 hp steps.
If you are working with a motor rather than a vehicle, two things follow. The nameplate kW is shaft output, so the electrical draw is higher — see HP to kW three-phase. And for circuit sizing you need current, not power: the motor full-load amps chart gives the code values by horsepower and voltage.
Mechanical HP vs Metric PS vs Electrical HP
"Horsepower" isn't a single unit. Mechanical (imperial) HP — the US and UK standard — equals 745.7 watts, so 1 kW = 1.341 HP. Metric horsepower (PS or CV), used on most European spec sheets, is slightly smaller at 735.5 watts, giving 1 kW = 1.3596 PS. Electrical HP is defined as exactly 746 watts. The differences are small but matter when you cross-check a manufacturer's figure: a 100 kW engine is 134.1 HP but 136.0 PS, which is why the same car can be advertised with two slightly different horsepower numbers in different markets.
Why Engines Are Rated in kW
Kilowatts are the SI unit of power and are standard across Europe, Australia, and most of the world for engine and motor ratings. Electric vehicles in particular are quoted in kW because it maps directly to battery and charger specs. Converting kW to horsepower lets you compare an EV or a metric-spec engine against traditional HP figures on an equal footing.
Worked Example
UK, Australian and Indian spec sheets label the same unit bhp, so kW to bhp gives the identical result with the registration-document context attached. For the metric power-to-weight comparison that usually follows, see kW per tonne.
Frequently Asked Questions
One kilowatt equals about 1.341 mechanical horsepower, or 1.36 metric horsepower (PS).
Multiply the kilowatts by 1.341 for mechanical horsepower. For metric PS, multiply by 1.3596.
100 kW is about 134 HP — typical for a mid-size family car. Performance cars often exceed 200 kW (268 HP).
Mechanical HP uses 1.341 per kW; metric PS uses 1.36 per kW. PS gives a slightly higher number, which is why European cars often quote PS.
Multiply mechanical horsepower by 0.7457 to get kilowatts.
1.006 hp — but in practice it is a 1 hp motor. 0.75 kW is the IEC standard size that corresponds to the NEMA 1 hp size; the two standards were deliberately aligned.
Because they follow a preferred number series — each step roughly 30–40% larger than the last. That gives 0.55, 0.75, 1.1, 1.5, 2.2, 3, 4, 5.5, 7.5 rather than round increments, mirroring NEMA's ½, ¾, 1, 1½, 2, 3 hp ladder.
2.95 hp — sold as a 3 hp motor. Likewise 1.5 kW is a 2 hp motor, 5.5 kW is 7.5 hp and 7.5 kW is 10 hp.
No — it is shaft output. Electrical input is higher because of efficiency and power factor. A 7.5 kW motor typically draws 8.3–8.8 kW, so sizing a supply from the nameplate alone undersizes the circuit.