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Power
Power Converter
Convert watts, kilowatts, horsepower, and more
Conversion Formula
Target = Value × (From Ratio / To Ratio)
Power conversions are linear ratio-based. Target = Value × (Source Ratio / Target Ratio). Watts, kilowatts, horsepower, and BTU/h are all supported.
Power conversion is essential in engineering, automotive, and energy sectors. Convert watts, kilowatts, megawatts, mechanical horsepower, metric horsepower (PS), and BTU per hour.
Horsepower was originally defined by James Watt to compare steam engine output to draft horses. One mechanical horsepower equals 745.7 watts.
All Supported Power Units
| Unit | Symbol | Definition |
|---|---|---|
| Watt | W | The SI unit of power, equal to 1 joule per second. |
| Milliwatt | mW | One-thousandth of a watt, used in low-power electronics. |
| Kilowatt | kW | One thousand watts, used for appliance power ratings and EV motors. |
| Megawatt | MW | One million watts, used for power plant output ratings. |
| Gigawatt | GW | One billion watts, used for large-scale power generation. |
| Horsepower (mechanical) | hp | An imperial unit of power equal to 550 foot-pounds per second. |
| BTU per hour | BTU/h | A power unit used in HVAC, equal to 1 BTU delivered per hour. |
| Metric Horsepower (PS) | PS | The metric unit of power, widely used in European automotive specifications. |
Common Power Conversions
| From | To | Value |
|---|---|---|
| 1 kW | hp | 1.341 |
| 1 hp | kW | 0.746 |
| 1 MW | kW | 1,000 |
| 1 PS | kW | 0.735 |
Frequently Asked Questions
Mechanical horsepower (hp) = 745.7 W. Metric horsepower (PS) = 735.5 W. PS stands for 'Pferdestärke' (German for 'horsepower').
BTU per hour is a power unit used in heating and cooling. 1 BTU/h ≈ 0.293 watts. A typical AC unit is rated at 12,000 BTU/h (~3.5 kW).
To convert kW to hp, multiply by 1.341. For example, 100 kW × 1.341 = 134.1 horsepower. This is commonly used for electric motor and engine specifications.
One kilowatt (kW) equals 1,000 watts (W). Kilowatts are used for larger power measurements like appliances and EV motors, while watts are used for smaller devices.
Typical appliances: LED bulb 10 W, laptop 50 W, refrigerator 150 W, microwave 1,000 W, air conditioner 3,500 W, electric oven 3,000 W, and water heater 4,500 W.
A megawatt (MW) equals 1,000,000 watts. It is used to measure power plant output, large wind turbines, and industrial machinery. One MW can power approximately 1,000 homes.
To convert watts to BTU per hour, multiply by 3.412. For example, 1,000 W × 3.412 = 3,412 BTU/h. This is essential for HVAC system sizing and comparison.