🔋 Power Converter
Convert power between watts, kilowatts, horsepower, and BTU per hour.
How power conversion works
Power is the rate of energy transfer, and this calculator converts a power value between the units used in engineering, automotive specs, and HVAC ratings. It converts your input to watts (the SI base unit) first, then converts that value into your chosen output unit.
Standard conversion factors are used: 1 mechanical horsepower = 745.699872 W, 1 BTU per hour = 0.29307107 W, and 1 kilocalorie per hour = 1.163 W. These match the accepted engineering definitions for horsepower and thermal power ratings.
This tool is provided for general educational and planning purposes, such as comparing engine, motor, or appliance power ratings across unit systems.
Last reviewed August 2026