Power Converter
Convert milliwatts, watts, kilowatts, megawatts, mechanical and metric horsepower, and BTU per hour.
· CalcFlow Editorial
1 hp = 0.74569987 kW
Results shown are estimates for informational purposes only. Nothing on CalcFlow is financial, tax, legal, or medical advice. Always consult a qualified professional before making important decisions.
Common Power Conversions
| Horsepower (mechanical) | Kilowatts | Milliwatts | Watts | Megawatts | Horsepower (metric) |
|---|---|---|---|---|---|
| 1 hp | 0.74569987 | 745,699.87 | 745.69987 | 0.00074569987 | 1.0138697 |
| 5 hp | 3.7284994 | 3,728,499.4 | 3,728.4994 | 0.0037284994 | 5.0693483 |
| 10 hp | 7.4569987 | 7,456,998.7 | 7,456.9987 | 0.0074569987 | 10.138697 |
| 50 hp | 37.284994 | 37,284,994 | 37,284.994 | 0.037284994 | 50.693483 |
| 100 hp | 74.569987 | 74,569,987 | 74,569.987 | 0.074569987 | 101.38697 |
| 150 hp | 111.85498 | 111,854,980 | 111,854.98 | 0.11185498 | 152.08045 |
| 200 hp | 149.13997 | 149,139,970 | 149,139.97 | 0.14913997 | 202.77393 |
| 500 hp | 372.84994 | 372,849,940 | 372,849.94 | 0.37284994 | 506.93483 |
| 1,000 hp | 745.69987 | 745,699,870 | 745,699.87 | 0.74569987 | 1,013.8697 |
Popular Power Conversions
Formula
watts = value x unit factor (1 hp = 550 ft-lbf/s = 745.6998715822702 W; 1 PS = 75 kgf-m/s = 735.49875 W)Understanding Power Conversion
Power is the rate of doing work, with the watt (one joule per second) as the SI unit. Engines are still rated in horsepower in many markets. Mechanical horsepower (used in the US and UK) is exactly 550 foot-pounds per second, about 745.7 W, while metric horsepower (PS or CV, used in continental Europe) is 75 kilogram-force meters per second, about 735.5 W. Air conditioners and furnaces are often rated in BTU per hour.
Tips and Best Practices
- 1Multiply horsepower by 0.7457 to get kilowatts.
- 2Multiply kilowatts by 1.341 to get mechanical horsepower.
- 3One BTU per hour is about 0.293 W.
Real-World Example
A 150 hp engine delivers 150 x 745.7 = 111.85 kW. A 12,000 BTU/h air conditioner draws about 12,000 x 0.29307 = 3,517 W of cooling capacity.
Common Mistakes to Avoid
- Treating metric and mechanical horsepower as the same; they differ by about 1.4 percent.
- Confusing BTU (energy) with BTU per hour (power).
- Reading a kW rating as kWh.
How to Use
- Pick the unit you have in the left selector and the unit you want in the right selector.
- Type a number in either box; the other box updates instantly.
- Use the swap button to reverse the direction and Copy result to copy the answer.
Frequently Asked Questions
How many watts are in a horsepower?
Is a PS the same as a hp?
How many kW is 100 hp?
Sources: NIST SP 811 (horsepower = 550 ft lbf/s; BTU_IT); DIN 66036 (metric horsepower = 75 kgf m/s with g_n = 9.80665 m/s2).