kW to HP Calculator & Conversion Chart

Kilowatts are the SI unit and appear on every EU registration document, but brochures, badges and everyday conversation still use horsepower. This page converts between them in both directions that matter — and gives you the full lookup table rather than a handful of round numbers.

Motor Sizes: 0.75 to 100 kW

Standard industrial motor ratings, which are specified in round kilowatt values across most of the world. Note how rarely they land on round horsepower numbers — a 75 kW motor is 100.58 HP, which is why the same motor is sold as "100 HP" in imperial markets.

Car and Engine Outputs: 100 to 500 kW

The range most vehicle specifications fall into. If you're reading a German, French or Italian brochure, the horsepower figure quoted is almost certainly the PS column, not mechanical HP.

Should You Use HP or PS?

It depends entirely on where the figure is going to be read.

• Mechanical HP (745.7 W) — the UK, US and Australia. Also written bhp.
• Metric PS (735.5 W) — Germany, France, Italy, Spain, Japan and most of continental Europe. Written KM in Poland, KS in Czechia and Croatia, pk in the Netherlands.

PS is about 1.4% smaller than mechanical horsepower, so the same engine always shows a slightly higher number in PS. A 150 kW car is 201 hp in Britain and 204 PS in Germany. Nothing about the engine differs. Our kW to PS converter covers the metric scale in depth, and hp vs bhp vs PS vs kW explains all four units.

Why Your Registration Document Shows kW

EU rules require engine power to be stated in kilowatts, because kW is the SI unit. Manufacturers keep printing PS on badges and in brochures because that's what buyers recognise. In several countries, vehicle tax and insurance bands are calculated from the kW figure, so if you're checking a bracket, work from the registration document rather than the boot lid.

Shortcuts Worth Memorising

• 1 kW ≈ 1.34 HP — accurate to better than 0.1%.
• 100 kW = 134 HP — the anchor everything else scales from.
• 75 kW = 100 HP — near enough exact, and the reason motor sizes cross over here.
• 1 HP ≈ 0.75 kW — the reverse, within 0.6%.

For single conversions the kW to HP calculator is quicker, and HP to kW handles the reverse. The full imperial-side table is on our HP to kW conversion chart, and the exact derivation of 0.7457 is in the exact HP to kW conversion.