Femtowatt is 1e-15 watt units.
Femtowatts to Metric horsepowers Converter — fW to PS
Convert Femtowatt (fW) to Metric horsepower (PS) using the exact conversion factor (1 femtowatt = 1.359622e-18 metric horsepower). See the formula, worked examples, conversion table, history, and common uses.
Femtowatts to Metric horsepowers converter
Converter
Power Converter
Convert watts, horsepower, refrigeration tons, BTU per hour, and engineering power units.
Context values
Some unit families need one extra value for a physically accurate result.
Metric horsepower.
Result = input x 1e-15 / 735.49875.
Power uses the watt as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Femtowatts to Metric horsepowers
Femtowatt and Metric horsepower both describe power output, and the conversion is a routine part of comparing an engine or motor's spec sheet across countries that use different power units. Specifically: Femtowatt is 1e-15 watt units, and metric horsepower.
Formula
metric horsepowers = femtowatts × 1.359622e-18
This factor comes from each unit's defined relationship to the category's base unit: 1 femtowatt equals 1e-15 base units, and 1 metric horsepower equals 735.49875 base units, so dividing one by the other gives the direct femtowatt-to-metric horsepower factor of 1.359622e-18.
Simple example
1 fW × 1.359622e-18 = 1.359622e-18 PS
1 femtowatt = 1.359622e-18 metric horsepowers.
Real-world example
100 fW × 1.359622e-18 = 1.359622e-16 PS
100 femtowatts = 1.359622e-16 metric horsepowers.
Conversion table
| Femtowatt (fW) | Metric horsepower (PS) |
|---|---|
| 1 fW | 1.359622e-18 PS |
| 10 fW | 1.359622e-17 PS |
| 100 fW | 1.359622e-16 PS |
| 500 fW | 6.798108e-16 PS |
| 1,000 fW | 1.359622e-15 PS |
| 5,000 fW | 6.798108e-15 PS |
Reverse conversion: Metric horsepower to Femtowatt
1.359622e-18 PS × 7.354987e+17 = 1.000000281 fW
1.359622e-18 metric horsepowers = 1.000000281 femtowatts.
femtowatts = metric horsepowers × 7.354987e+17
For a page dedicated to this direction, see Metric horsepower to Femtowatt.
Understanding the Femtowatt (fW)
Femtowatt is 1e-15 watt units.
Understanding the Metric horsepower
Metric horsepower (PS) measures power. Metric horsepower (PS/CV) is defined as exactly 735.49875 watts, the power to raise 75 kilograms one meter per second. It is classified as a Non-SI unit (metric, automotive).
Where it's used: Continental Europe, Japan, and other metric-system automotive markets
Uses of the Metric horsepower today
- European and Japanese vehicle engine power ratings (often shown as PS or CV)
- Motor and machinery power specifications in metric countries
History of the Metric horsepower
Metric horsepower emerged in continental Europe in the 19th century as engineers sought a metric-system analog to Watt's English horsepower, defining it via a round figure (75 kgf·m/s) convenient in metric calculations. It remains the standard automotive power unit across much of Europe and Asia, labeled PS (German 'Pferdestärke') or CV (French/Italian 'cheval-vapeur').
Historical origin. Metric horsepower was not the invention of a single named person; it developed through the process described above.
Metric horsepower — sources
- NIST Special Publication 811 — Documents the exact watt-equivalence of metric horsepower.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many metric horsepowers are in 1 femtowatt?
1 femtowatt equals 1.359622e-18 metric horsepowers, using the exact defined conversion factor rather than an estimate.
How do I convert femtowatt to metric horsepower?
Multiply the femtowatt value by 1.359622e-18. The converter above does this instantly to whatever precision you set.
How do I convert metric horsepower back to femtowatt?
Use the reverse factor: 1 metric horsepower equals 7.354987e+17 femtowatts. You can also use the swap control in the converter above to flip the direction instantly.
What is a femtowatt?
Femtowatt (fW) is a unit of power.
What is a metric horsepower?
Metric horsepower (PS) measures power. Metric horsepower (PS/CV) is defined as exactly 735.49875 watts, the power to raise 75 kilograms one meter per second. It is classified as a Non-SI unit (metric, automotive).
Is the femtowatt to metric horsepower conversion exact?
Yes. Metric horsepower (PS/CV) is defined as exactly 735.49875 watts, the power to raise 75 kilograms one meter per second. That fixed definition is what the converter above uses, so any rounding you see is a display choice, not a limitation of the math.