HP to PS Converter

Convert between imperial horsepower (HP/BHP) and metric horsepower (PS, pk, cv, ch, hk) — with kilowatts alongside.

HP ↔ PS Converter
RESULT

European, Japanese and Korean car specs quote metric horsepower — written PS in Germany and Japan, pk in the Netherlands, ch/cv in France and Spain, hk in Scandinavia. Imperial (mechanical) horsepower is the US/UK unit. They differ by about 1.4%, enough to matter when comparing spec sheets.

Quick answer: 1 HP = 1.0139 PS, and 1 PS = 0.9863 HP. So a "300 PS" German spec is 296 imperial HP, and a 300 HP American car is 304 PS.

HP to PS Formula

Conversions
PS = HP × 1.01387  |  HP = PS × 0.98632
From the definitions: 1 HP = 745.70 W, 1 PS = 735.50 W (75 kgf·m/s).

Why Two Horsepowers Exist

James Watt defined horsepower as 550 ft-lb/sec (745.7 W). When continental Europe metricated, engineers redefined it as the power to lift 75 kg one metre per second — 735.5 W — and called it Pferdestärke (PS, "horse strength"). Every country then translated the name: pk (paardenkracht), cv (cavallo vapore / caballo de vapor), ch (cheval-vapeur), hk (hästkraft). They are all the same 735.5 W metric unit — only the imperial HP differs.

Marketing exploits the gap: quoting PS makes the same engine sound ~1.4% stronger. EU type-approval documents use kW officially; see our HP to kW converter for that leg.

HP ↔ PS Conversion Table

HPPSkW
100101.474.6
150152.1111.9
200202.8149.1
300304.2223.7
400405.5298.3
500506.9372.9
750760.4559.3
10001013.9745.7

Worked Example

Worked Example
1. A German spec sheet says 421 PS
2. HP = 421 × 0.98632 ≈ 415 HP
3. kW = 421 × 0.7355 ≈ 310 kW
How this calculator is checked

Uses the exact definitions 1 HP = 745.70 W and 1 PS = 735.49875 W (75 kgf·m/s), giving the factor 1.01387. Exact unit conversion.

Frequently Asked Questions

Almost — PS is about 1.4% smaller. 100 PS = 98.6 HP. For rough comparisons they're interchangeable; for exact figures, convert.

Yes. They're the Dutch, Italian/Spanish, French and Scandinavian names for the identical 735.5 W metric horsepower.

100 kW = 136.0 PS = 134.1 HP. Divide kilowatts by 0.7355 for PS, or by 0.7457 for imperial HP.

BHP (brake horsepower) is imperial HP measured at the crank — so BHP to PS uses the same ×1.0139 factor. See our brake horsepower page.