Convert horsepower to kilowatts (hp to kW)
To convert horsepower to kilowatts, multiply the value in horsepower by 0.74569987158227 (about 0.7457). Car buyers, mechanics and engineers use it to compare engine and motor ratings between US or UK specs and metric datasheets. This hp to kw converter works both ways: type horsepower or kilowatts into either box above and the other box, the worked formula and the chart below update as you type.
Mechanical horsepower (hp) was defined by James Watt as 550 foot-pounds per second, which works out at 745.69987158227 watts. It is the familiar rating for car and motorcycle engines in the US and UK, and for lawn mowers, pumps and outboard motors. One horsepower is 0.7457 kilowatts.
The kilowatt (kW) is 1,000 watts. The watt, also named after James Watt, is the SI unit of power: one joule per second. Going the other way, one kilowatt equals 1.34102 horsepower. Kilowatts are used for electric motors, EV chargers, solar systems, generators and, officially, car engines in Europe.
How to convert hp to kw with this tool
- Type a number into the Horsepower (hp) box — it starts at 150 hp as an example.
- Read the answer in the Kilowatts (kW) box and in the result panel, which also shows the formula with your number.
- To go the other way, type into the kilowatts box, or press the swap button to open the kW to HP converter with your value carried over.
- Choose how many decimal places you want, or tap a quick value such as 5 hp, 100 hp, 150 hp.
- Press Copy result to paste the conversion into a message, spreadsheet or note.
HP to kW converter features
Converts both ways
Type in the horsepower box to get kilowatts, or in the kilowatts box to get horsepower. The other box follows instantly.
Exact factor
Calculations use 1 hp = 0.74569987158227 kW, and rounding is applied only to the answer you see — choose Auto or 0–10 decimal places.
Formula with your number
The working is shown under the result, for example 150 hp × 0.74569987158227 = 111.855 kW, so you can check it or copy the method.
Quick values and chart
Tap common values like 5 hp, 100 hp, 150 hp, or read the horsepower-to-kilowatts table further down this page.
Metric horsepower too
European specs often quote PS or CV; the line under the result converts metric horsepower to kW as well.
HP to kW formula
The formula is kW = hp × 0.74569987158227. It is exact because one mechanical horsepower is 745.69987158227 W, or 0.74569987158227 kW.
The reverse formula is hp = kW ÷ 0.74569987158227 — or use the kW to HP converter. Three worked examples:
- A 150 hp car engine: 150 hp × 0.74569987158227 = 111.855 kW
- A 5 hp lawn mower: 5 hp × 0.74569987158227 = 3.7285 kW
- A 300 hp sports car: 300 hp × 0.74569987158227 = 223.71 kW
Which horsepower?
Several units share the name horsepower, so check which one a spec sheet means. For example, 100 hp = 74.57 kW, while 100 PS = 73.5499 kW. The common ones are:
- Mechanical (imperial) horsepower, hp — 745.69987158227 W. Used on this page and for engines in the US and UK.
- Metric horsepower (PS, CV, ch) — 735.49875 W, about 1.4% smaller; common in Europe and Asia.
- Electrical horsepower — exactly 746 W, used to rate electric motors.
- Boiler horsepower — about 9,810 W, used only for steam boilers.
HP to kW quick reference
The values people look up most often, worked out with the exact factor:
- 1 hp = 0.7457 kW
- 1 kW = 1.34102 hp
- 5 hp = 3.7285 kW
- 100 hp = 74.57 kW
- 150 hp = 111.855 kW
- 200 hp = 149.14 kW
Quick tip: Multiply by 3/4 for a quick estimate: 200 hp ≈ 150 kW, close to the exact 149.14 kW.
Related conversions: the full power converter.
HP to kW conversion table
Values in kilowatts are rounded to 4 decimal places (more for very small numbers). For any value not listed, type it into the converter above.
| hp | kW | hp | kW |
|---|---|---|---|
| 1 | 0.7457 | 125 | 93.2125 |
| 2 | 1.4914 | 150 | 111.855 |
| 3 | 2.2371 | 175 | 130.4975 |
| 5 | 3.7285 | 200 | 149.14 |
| 7.5 | 5.5927 | 250 | 186.425 |
| 10 | 7.457 | 300 | 223.71 |
| 15 | 11.1855 | 350 | 260.995 |
| 20 | 14.914 | 400 | 298.2799 |
| 25 | 18.6425 | 450 | 335.5649 |
| 50 | 37.285 | 500 | 372.8499 |
| 75 | 55.9275 | 600 | 447.4199 |
| 100 | 74.57 | 700 | 521.9899 |
| 110 | 82.027 | 1,000 | 745.6999 |
| 120 | 89.484 |
HP to kW FAQ
What is 100 hp in kilowatts?
100 horsepower is 74.57 kilowatts: 100 hp × 0.74569987158227 = 74.57 kW.
How do I convert hp to kw?
Multiply the value in horsepower by 0.74569987158227 (about 0.7457). For example, 200 hp × 0.74569987158227 = 149.14 kW. To convert back, divide the value in kilowatts by 0.74569987158227 — or use the kW to HP converter.
What is 1 kW in horsepower?
One kilowatt is 1.341 horsepower, because 1 kW ÷ 0.74569987158227 = 1.341 hp.
What does 200 hp equal in kilowatts?
Is PS the same as hp?
Not quite. PS (Pferdestärke, metric horsepower) is 735.49875 W, about 1.4% less than mechanical horsepower. 100 PS is 73.5499 kW, while 100 hp = 74.57 kW. The PS figure is shown under the result.