What is a Metric Horsepower?

The Pferdestärke (PS), also called metric horsepower or 'cheval vapeur' (CV) in French, equals exactly 735.49875 watts — about 1.4% smaller than mechanical horsepower. Defined as the power needed to lift 75 kg by 1 meter in 1 second under standard gravity, the PS is the European traditional power unit for car engines. German, French, Italian, and Japanese car manufacturers historically rated engines in PS, and the unit persists in marketing — '300 PS' sounds slightly higher than '300 hp' to consumers. EU regulations require power to be specified primarily in kW, with PS allowed as a secondary unit. The PS relates to the watt (1 PS ≈ 735.5 W), the kilowatt (1 PS ≈ 0.7355 kW), and the mechanical horsepower (1 PS ≈ 0.9863 hp). The slight difference between PS and hp is mostly imperceptible in casual use but noticeable in precise engineering specifications.

Visual reference for how the metric horsepower relates to other power units. Each row links to the full converter for that pair.

• European car and motorcycle ratings
• Italian and German engine specs
• Some European industrial equipment

• ✓1 PS = 735.5 W = 0.9863 hp.
• ✓PS is ~1.4% smaller than mechanical hp.
• ✓Look for "PS" in German car brochures; "ch" in French.

• ✗Treating PS and hp as equal — 1.4% off.
• ✗Using PS in US markets — unfamiliar to consumers.
• ✗Mixing PS and kW without conversion.