kW to BHP Converter

The conversions used

1 kW equals 1.34102 bhp, and 1 kW equals 1.35962 PS, which makes 1 PS equal to 0.98632 bhp. These come from the underlying SI definitions - 1 bhp (imperial mechanical horsepower) is exactly 745.69987 W, and 1 PS (metric horsepower) is exactly 735.49875 W - so the calculator above and every figure on this page use full precision internally and round only for display, to one decimal place.

Worked example: a 110 kW engine

A spec sheet or V5C logbook quoting 110 kW converts to bhp as 110 × 1.34102 = 147.51, which rounds to 147.5 bhp. In PS that's 110 × 1.35962 = 149.56, rounding to 149.6 PS. As a check, converting the unrounded PS figure back gives 149.5582 × 0.98632 = 147.512, which also rounds to 147.5 bhp, confirming the two routes agree - starting from the already-rounded 149.6 instead gives 147.6, a 0.1 double-rounding artefact from rounding twice, not a sign the constants disagree.

Why the UK talks in bhp but EU spec sheets quote kW or PS

Brake horsepower is the older imperial measure and it's what UK car culture, tuners and classified adverts have quoted for decades, so it's the number most UK buyers recognise. Kilowatts are the SI unit and the one that appears on official type-approval paperwork across the EU and UK alike, which is why continental manufacturers' brochures and technical datasheets lead with kW. Many of those same brochures also quote PS, the metric near-equivalent of bhp used historically in Germany and much of Europe, so a single engine can appear with three different-looking numbers depending on which document you're reading - they're all the same power, just in different units.

bhp vs PS: why quoted power differs between markets

The gap between bhp and PS is small but real - only about 1.4%, since 1 PS is 0.98632 bhp. That's why a car marketed at 150 PS in a German or Japanese brochure is 147.9 bhp, and it's a common source of confusion when comparing the "same" engine's output across a UK listing and an import spec sheet. Neither figure is wrong; they're measuring the same power in different historical units, and the difference is exactly the 1.4% conversion factor, not a difference in the engine itself.

bhp vs wheel horsepower: what a dyno actually measures

The bhp or kW figure on a spec sheet is measured at the engine (or crank), before the power reaches the wheels. A rolling-road dyno instead measures power at the wheels, after it has passed through the gearbox, differential and driveshafts, all of which absorb some of it as friction and heat. That loss is typically quoted as 10-20% depending on the drivetrain - a manual front-wheel-drive car sits toward the low end, a four-wheel-drive car with more rotating mass toward the high end - but dyno figures vary between rolling roads and run conditions, so there's no single precise number to convert one to the other. Treat a wheel horsepower reading as a real-world snapshot rather than something directly comparable to a manufacturer's crank figure.

Why your V5C or insurance renewal lists power in kW

The V5C registration certificate and most UK insurers record engine power in kW because that's the unit used in the vehicle's official type-approval data, the same source the DVLA pulls from. If a quote or renewal form only gives you a kW figure and you want the bhp number you'd recognise from a brochure or classified advert, that's exactly what the calculator above converts - type the kW figure in and read off bhp and PS immediately.

Related tools

Converting a torque figure rather than a power figure, or working out bhp from Nm and rpm off a dyno printout? The torque and power converter covers bhp to Nm, PS to bhp and lb-ft to Nm in one page. To compare the converted output with vehicle mass, continue to the power to weight calculator. With the power figure converted, the 0-60 calculator estimates what it means for acceleration.