Power Converter
Convert power between watts, kilowatts, horsepower, BTU per hour and tons of refrigeration — enter one value and read it in every unit at once.
Watts, Horsepower and BTUs
Power is the rate of doing work or moving energy, and it shows up under many names: electrical loads in watts and kilowatts, engines in horsepower, heating and cooling in BTU per hour or tons of refrigeration. They are all the same quantity, related by fixed factors.
| Equivalent | Value |
|---|---|
| 1 HP (mechanical) | 745.7 W = 0.7457 kW |
| 1 kW | 1.341 HP = 3,412 BTU/hr |
| 1 ton refrigeration | 3.517 kW = 12,000 BTU/hr |
| 1 BTU/hr | 0.2931 W |
Frequently Asked Questions
Mechanical vs metric horsepower?
Mechanical (US) horsepower is 745.7 W; metric horsepower (PS) is 735.5 W, about 1.4 percent less. European car specs often use PS.
What is a ton of refrigeration?
A cooling power of 12,000 BTU/hr, or 3.517 kW – the rate that melts one short ton of ice in 24 hours. It is standard in HVAC sizing.
Is this real or apparent power?
Real power, in watts. Apparent power in VA only equals watts at unity power factor; use the power-factor tools for AC loads.
Related calculators
- Pump Horsepower Calculator — power to move a fluid.
- Three-Phase Power Calculator — real, reactive and apparent power.
- Engineering Unit Converter — the all-in-one converter.