Power Converter
Convert power between watts, kilowatts, horsepower and BTU/hour.
Results update as you type.
About this calculator
A power converter changes a rate of energy use between watts, kilowatts and megawatts, mechanical and metric horsepower, and BTU per hour. All values convert through the watt as the base unit.
Frequently asked questions
How many watts are in one horsepower?
One mechanical horsepower is about 745.7 watts. Metric horsepower (PS) is slightly less, about 735.5 watts, which is why the same engine can show two different figures.
How do kilowatts relate to horsepower?
One kilowatt is about 1.341 mechanical horsepower. Electric-car motors are often rated in kW, so a 150 kW motor is roughly 201 hp.
What is BTU per hour?
BTU/hour rates heating and cooling equipment. One watt equals about 3.412 BTU/h, so a 3.5 kW air conditioner is roughly 12,000 BTU/h — a "1 ton" unit.
Results are estimates for general guidance only, not financial, medical or tax advice.