Power Converter
Convert power between watts, kilowatts, megawatts, horsepower, metric PS, BTU/h and more, with instant both-way results.
About the Power Converter
This power converter switches between the units used in electrics, engines and heating: watts, kilowatts, megawatts, mechanical horsepower, metric horsepower (PS), BTU per hour, foot-pounds per second and calories per second. Enter a value, choose your units, and the answer appears instantly.
Power is the rate of energy use. The watt is the SI unit; car and motor output is often quoted in horsepower (mechanical hp ≈ 745.7 W, metric PS ≈ 735.5 W); and heating and cooling equipment uses BTU per hour. Having them together makes cross-industry comparisons simple.
All conversions use exact factors through a watt base unit and run locally in your browser for fast, precise results.
How to Use the Power Converter
- 1Enter the power value to convert.
- 2Select the source and target units.
- 3Read the result and reverse conversion instantly.
- 4Use the reference table for common values.
Frequently Asked Questions
How many watts is one horsepower?
Mechanical (imperial) horsepower is about 745.7 watts, while metric horsepower (PS or CV) is about 735.5 watts. So a 100 hp engine is roughly 74.6 kW. Car specs vary on which horsepower they mean, so this converter offers both.
How do I convert kW to hp?
Divide kilowatts by 0.7457 to get mechanical horsepower (or by 0.7355 for metric PS). So 150 kW is about 201 hp. To go from hp to kW, multiply by those factors. The tool handles both directions and both horsepower definitions.
What is BTU/h and why is it used for air conditioners?
BTU per hour is a rate of heat energy — how fast a system heats or cools. Air conditioners and heaters are rated this way; a 12,000 BTU/h unit ('one ton') is about 3.5 kW. This converter relates BTU/h to watts so you can compare appliance ratings.
What's the difference between power and energy?
Energy (joules, kWh) is a total quantity; power (watts) is the rate of using it. A 2000 W heater running for one hour uses 2 kWh of energy. This tool converts power units; use the Energy Converter for joules, kWh and calories.
Where is power conversion useful?
Comparing engine and motor outputs across markets (hp vs kW vs PS), sizing HVAC equipment (BTU/h to kW), electrical engineering, and physics problems. Moving fluently between watts and horsepower is essential when working across metric and US specifications.