Convert Metric Horsepower to Horsepower
Metric horsepower to horsepower is the conversion you need when a European car is rated in PS (also written CV or 'Pferdestärke') and you want the mechanical horsepower figure the US and UK use. One metric horsepower is approximately 0.98632 mechanical horsepower, so the number drops slightly when you switch over.
Metric horsepower (PS) to Horsepower (mechanical) conversion table
| Metric horsepower (PS) (PS) | Horsepower (mechanical) (hp) |
|---|---|
| 1 | 0.98632 |
| 2 | 1.97264 |
| 3 | 2.95896 |
| 5 | 4.9316 |
| 10 | 9.863201 |
| 20 | 19.726401 |
| 50 | 49.316004 |
| 100 | 98.632007 |
| 500 | 493.160035 |
| 1,000 | 986.320071 |
The formula
To convert metric horsepower to mechanical horsepower, multiply the number of metric horsepower by 0.98632:
horsepower = metric horsepower × 0.98632
A worked example
Say you have a 150 PS car and want its power in mechanical horsepower:
150 × 0.98632 = 147.94801 hp
So 150 metric horsepower is about 147.95 mechanical horsepower.
Why it's an approximation
The two "horsepower" units aren't the same size. Metric horsepower (PS, or CV, from the German "Pferdestärke") is defined as exactly 735.49875 W, and it's the figure printed on European car and motorcycle spec sheets. Mechanical horsepower — the one used in the US and UK — is about 745.7 W. Because the metric unit is roughly 1.4% smaller, one metric horsepower comes out to approximately 0.98632 mechanical horsepower. The two are defined from different bases, so they don't divide evenly and the factor stays rounded.
When you'll use it
Comparing a European car's PS rating against the horsepower figures used in US and UK reviews, translating an imported vehicle's power onto a spec sheet you're used to, and any time you need to line up a metric-horsepower number with mechanical horsepower.
Frequently asked questions
How many mechanical horsepower are in one metric horsepower?
About 0.98632 hp. Metric horsepower (PS) is defined as exactly 735.49875 W, while mechanical horsepower is about 745.7 W — so the metric figure is roughly 1.4% smaller, and the conversion factor is rounded.
Why is a car's PS number higher than its hp number?
Because metric horsepower is a smaller unit. Each metric horsepower is about 0.98632 mechanical horsepower, so the same engine shows a slightly higher count in PS than in hp — it's the unit that changed, not the power.
Is the metric horsepower to horsepower conversion exact?
No. Metric horsepower and mechanical horsepower are defined from different bases, so the factor 0.98632 is rounded. More decimal places give you more precision if you need it.