Power Converter
Convert power units: Watts (W), Kilowatts (kW), Horsepower (hp), Megawatts (MW), and BTUs per hour.
Power Converter: Watts, Kilowatts, Horsepower, BTU/hr & Megawatts
Power measures the rate at which energy is transferred or work is performed over time. In electrical appliances, electric vehicles, renewable solar arrays, and combustion engines, power ratings appear in diverse units: mechanical horsepower (hp) for automotive engines, Watts (W) and Kilowatts (kW) for electrical circuits, and BTU per hour for HVAC thermal systems.
ToolQix Power Converter provides seamless transitions between mechanical, electrical, and thermal power scales. Convert instantly between Watts (W), Kilowatts (kW), Megawatts (MW), Metric Horsepower (PS/CV), Mechanical Horsepower (hp), BTU per hour (BTU/hr), Foot-Pounds per minute, and Tons of Refrigeration.
Watt (J/s) Base Standard & Mechanical Horsepower Derivation
In the SI system, power is measured in Watts (W), named after James Watt, where one Watt equals one Joule of energy expended per second (1 W = 1 J/s). Mechanical horsepower was originally established by James Watt to compare steam engines against draft horses, defined as 33,000 foot-pounds of work per minute (approx. 745.69987 Watts).
How to Use Power Converter Step-by-Step
Select Source & Target Power Units
Choose your input unit (e.g., Horsepower hp) and desired destination unit (e.g., Kilowatts kW).
Input Power Value
Enter any numeric power rating into the input field.
Review Multi-Scale Grid
View converted ratings across electrical watts, automotive horsepower, and HVAC thermal outputs.
Copy Converted Rating
Copy your result directly to the clipboard with customizable decimal precision.
Power Converter Industry Use Cases
Electric Vehicle (EV) vs ICE Comparisons
Compare electric vehicle motor output ratings quoted in Kilowatts (kW) against traditional gasoline horsepower (hp).
Solar Panel & Generator Sizing
Calculate household peak wattage demands to size backup emergency generators and solar inverter capacities.
HVAC Thermal Heating & Cooling
Convert residential heating furnace output from BTU/hr into electrical equivalent kilowatts.
Industrial Electric Motors & Pumps
Translate industrial motor nameplates between standard US horsepower and IEC metric kilowatts.
Power Converter Best Practices & Tips
- Remember the golden automotive conversion: 1 Horsepower (mechanical hp) is approximately 0.746 Kilowatts (kW).
- Conversely, to convert electric vehicle kW to horsepower, multiply by 1.341 (e.g., a 150 kW EV motor delivers ~201 hp).
- Distinguish between Imperial Mechanical Horsepower (745.7 W) and European Metric Horsepower (PS/CV = 735.5 W).
- Do not confuse power (rate of energy, Watts) with energy (total work done, Watt-hours): a 100W light bulb running for 10 hours consumes 1,000 Wh (1 kWh) of energy.
Standard Power Unit Conversion Multipliers
| Power Unit | Symbol | Watts (W) | Kilowatts (kW) | Horsepower (hp) | BTU/hr |
|---|---|---|---|---|---|
| Watt (SI Base) | W | 1.0 W | 0.001 kW | 0.001341 hp | 3.41214 BTU/hr |
| Kilowatt | kW | 1,000 W | 1.0 kW | 1.34102 hp | 3,412.14 BTU/hr |
| Horsepower (Mechanical) | hp | 745.7 W | 0.7457 kW | 1.0 hp | 2,544.43 BTU/hr |
| Horsepower (Metric PS) | PS | 735.5 W | 0.7355 kW | 0.98632 hp | 2,509.63 BTU/hr |
| Megawatt | MW | 1,000,000 W | 1,000 kW | 1,341.02 hp | 3,412,142 BTU/hr |
| BTU per Hour | BTU/hr | 0.29307 W | 0.000293 kW | 0.000393 hp | 1.0 BTU/hr |
FAQs About Power Converter
How many kilowatts are in one horsepower?
One mechanical horsepower equals approximately 0.7457 kilowatts (745.7 Watts). Conversely, one kilowatt equals approximately 1.341 horsepower.
What is the difference between mechanical horsepower and metric horsepower?
Mechanical horsepower (hp, used in the US and UK) equals 550 foot-pounds per second (~745.7 Watts). Metric horsepower (PS in Germany, CV in France/Italy) is defined as the power to lift 75 kg against gravity by 1 meter in 1 second (~735.5 Watts), making metric horsepower roughly 1.4% smaller.
What is the difference between power and energy?
Power is the instantaneous rate of doing work (measured in Watts or Horsepower). Energy is the total cumulative work performed over time (measured in Joules or Watt-hours). Think of power as speed (miles per hour) and energy as distance traveled (total miles).
How much horsepower is a 300 kW electric car?
Multiply 300 kW by 1.341: 300 × 1.341 ≈ 402.3 horsepower.
Is any power data entered here stored on external servers?
No. ToolQix processes all calculations locally inside your web browser.
Tested Methodology & Client-Side Processing
Reviewed: October 21, 2026Calculations, algorithms, and transformations in this utility run directly in your browser without sending your private inputs to remote processing servers. Formulas reference established technical specifications and official documentation under our Editorial & Testing Policy.