Horsepower to Metric Horsepower
An instant horsepower-to-metric horsepower converter, with the formula and a reference table below.
| Horsepower | Metric Horsepower |
|---|---|
| 1 hp | 1.01387 PS |
| 2 hp | 2.027739 PS |
| 3 hp | 3.041609 PS |
| 5 hp | 5.069348 PS |
| 10 hp | 10.138697 PS |
| 25 hp | 25.346742 PS |
| 50 hp | 50.693483 PS |
| 100 hp | 101.386967 PS |
How to use
- Enter a value in the Horsepower field.
- The Metric Horsepower figure appears immediately — no button to press.
- Typing in the Metric Horsepower field converts back to Horsepower the same way.
- Use the reference table for the values that come up most often.
Horsepower to Metric Horsepower formula
The factor from horsepower to metric horsepower is 1.01386967.
PS = hp × 1.01386967
Why this factor: the horsepower and the metric horsepower are both defined against the watt, so dividing one definition by the other gives 1.01386967 directly. Both definitions are set out in full below.
To go the other way, divide by 1.01386967 — or use the Metric Horsepower to Horsepower converter, which is the same calculation reversed.
Worked example
Given 150 hp, multiplying by 1.01386967 yields 152.08045 PS.
150 hp × 1.01386967 = 152.08045 PS
The converter above does this for any value you type, in either direction.
What is a horsepower?
Mechanical horsepower is the traditional English-speaking unit of engine power.
Definition: Defined as 550 foot-pounds per second, which is about 745.700 watts.
Where it is used: US and UK car, motorcycle and small-engine power ratings.
Worth knowing: Distinct from metric horsepower (PS), which is about 1.4% smaller — so the same engine scores slightly higher in PS than in hp.
What is a metric horsepower?
Metric horsepower, written PS or CV, is the continental European engine power unit.
Definition: Defined as 75 kilogram-force meters per second, which is exactly 735.49875 watts.
Where it is used: German, French, Italian and Japanese vehicle specifications, where power is quoted in PS, CV or ps.
Worth knowing: About 98.6% of a mechanical horsepower, which is why converted figures never come out as round numbers.
Horsepower vs Metric Horsepower
The horsepower is an imperial unit while the metric horsepower is a metric unit. That is why the factor between them is not a round number: the two systems were defined independently and only later tied together by exact agreement.
Frequently asked questions
How many metric horsepower are in a horsepower?
One horsepower equals 1.01386967 metric horsepower.
What is the formula to convert horsepower to metric horsepower?
Multiply the number of horsepower by 1.01386967. To reverse it, divide by 1.01386967 instead.
How do I convert metric horsepower back to horsepower?
Divide by 1.01386967, which is the same as multiplying by 0.986320071.
How many metric horsepower are in 10 horsepower?
10 hp works out to 10.138697 PS.
Is there anything to watch out for with horsepower?
Distinct from metric horsepower (PS), which is about 1.4% smaller — so the same engine scores slightly higher in PS than in hp.
How is the horsepower defined?
Defined as 550 foot-pounds per second, which is about 745.700 watts.