Donaldson R F Power Converter
kW, horsepower (mechanical, metric and electrical) and BTU/h — not all "horsepower" is the same unit.
How this is worked out
"Horsepower" isn't one single unit — the mechanical (imperial/SAE) horsepower, used for cars and engines in the UK and US, equals exactly 745.699872 W; the metric horsepower (CV in French/Spanish, PS in German), common across much of Europe and Japan, is a different, slightly smaller unit, exactly 735.49875 W; and the electrical horsepower, used for electric motor ratings in the US, is defined as exactly 746 W. Mixing these up gives a small but real error (about 1.4% between mechanical and metric horsepower), which is why a car's "160 hp" and "162 CV" can describe the same engine.
Frequently asked questions
Which horsepower does a UK or US car's spec sheet use?
Usually mechanical horsepower (sometimes called brake horsepower, bhp) — European manufacturers often quote the same engine's output in CV/PS instead, which is why the same car can show different-looking numbers in different markets for what's physically the same power.
Why is BTU/h included here?
It's the traditional unit for air conditioner and heating capacity in several countries, so it's useful to compare directly against a kW or horsepower rating for the same equipment.
Related tools: HVAC / BTU Calculator, Unit Converter, Electricity Cost Calculator.
Source / Last verified: standard exact unit definitions — mechanical horsepower = 745.699872 W (33,000 ft·lbf/min), metric horsepower (CV/PS) = 735.49875 W (75 kgf·m/s), electrical horsepower = 746 W exactly, BTU/h = 0.29307107 W (International Table BTU, exact) — read/checked 1 October 2026, cross-checked against multiple independent engineering reference conversion tables that agree exactly on these figures.