Enter a power value, pick the unit you have and the unit you want, and read the answer instantly — plus the same value in every other unit at once. It keeps mechanical horsepower (hp) and metric horsepower (PS) separate, which matters for car engines, and includes BTU/h for heating and cooling gear. Everything runs in your browser.
In all units
- Watt (W)1,000 W
- Kilowatt (kW)1 kW
- Megawatt (MW)0.001 MW
- Horsepower, mechanical (hp)1.341022 hp
- Horsepower, metric (PS/KS)1.359622 PS
- BTU per hour (BTU/h)3,412.141633 BTU/h
How it works
Each unit is defined by how many watts it equals, and every conversion goes through the watt as a shared base. Your value becomes watts and then the target unit, so results stay consistent — converting kW to PS and back returns exactly what you started with.
The two horsepowers are not the same: mechanical (imperial) horsepower is about 745.70 W, while metric horsepower — the PS or “KS” quoted for European cars — is 735.49875 W. That’s why the same engine reads a few percent higher in PS than in hp. BTU/h (used on air conditioners) is about 0.293 W.
Practical examples
Car engine from kW to PS
A 100 kW engine is about 136 PS (metric horsepower) — the figure a European brochure would print. Enter 100, from kW, to PS.
US spec in hp to kW
A 300 hp American car is about 224 kW. Convert mechanical horsepower to kilowatts to compare it with a metric registration document.
Air conditioner in BTU/h to kW
A 12,000 BTU/h unit is about 3.5 kW of cooling power. Convert BTU/h to kilowatts to compare cooling capacity with a unit rated in kW.
Frequently asked questions
How many horsepower are in a kilowatt?
About 1.341 mechanical hp, or 1.360 metric PS. So 100 kW is roughly 134 hp but 136 PS. The tool shows both because a spec sheet may use either, and mixing them up shifts the number by around 1.4%.
What is the difference between hp and PS?
Mechanical horsepower (hp), the imperial unit, is about 745.70 W. Metric horsepower (PS, from German Pferdestärke, also written KS or KS locally) is defined as 735.49875 W. European car figures are almost always PS; US figures are hp.
Is PS the same as the local “KS”?
Yes. KS (konjska snaga) is the Serbian name for metric horsepower, identical to the German PS. A car listed as 150 KS is 150 PS, about 110 kW or 148 mechanical hp.
How do I convert kW to hp for a car?
Multiply kilowatts by about 1.36 for metric PS (the usual European figure) or by 1.341 for mechanical hp. For example 74 kW ≈ 100 PS. Just pick the units and the tool does it exactly.
What is BTU/h and why is it a power unit?
BTU per hour is energy (British thermal units) delivered per unit time, which is power. Air conditioners and heaters are rated in BTU/h in the US; 12,000 BTU/h (“one ton” of cooling) is about 3.5 kW.
What’s the difference between kW and kWh?
kW is power — the rate of energy use right now. kWh is energy — power used over time. A 2 kW heater running for 3 hours uses 6 kWh. This tool converts power (kW); for the energy total use an energy converter.
Does it accept the decimal comma?
Yes. You can type 74,5 or 74.5 and both mean the same. Grouping separators in pasted numbers are read too, so 1.000 is understood as one thousand.
How precise are the results?
Conversions run at full floating-point precision using the exact horsepower and BTU definitions and are shown to six decimals with trailing zeros trimmed.
Are the values I enter sent anywhere?
No. The conversion runs entirely in your browser; nothing is uploaded and analytics never receives the numbers.
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