Power Converter
Convert watts, kilowatts, horsepower, and BTU/hr.
Unit
Power Converter
Generated on April 24, 2026
?What is the Power Converter?
A power converter moves between watts, kilowatts, horsepower, metric horsepower (PS), and BTUs per hour. Power is the rate of energy use — 1 watt is 1 joule per second. Electronics are rated in watts, cars in horsepower, air conditioners in BTU/hr, and power stations in megawatts. Being able to translate between these is crucial when comparing a Japanese car's 150 PS to an American car's 148 hp, sizing an air conditioner by BTU/hr when only kilowatts are quoted, or planning a solar installation in kW vs. the family's 200 W appliance load.
The Formula
Power is work per unit time, with the watt as the SI base. James Watt defined mechanical horsepower in 1782 to market his steam engine by comparison with a draft horse — his figure was 33,000 ft-lb per minute, which equals 745.7 W. Metric horsepower (PS, Pferdestärke) uses kilogram-meters instead, producing a slightly smaller 735.5 W. For heating and cooling equipment, the BTU per hour is standard in the US and UK; 3,412 BTU/hr equals exactly 1 kW of thermal power.
Practical Examples
A 100-horsepower car engine delivers about 74.57 kW — the typical output of a small sedan.
A 12,000 BTU/hr air conditioner (colloquially '1 ton of cooling') is roughly 3.5 kW — enough for a 350–450 sq ft room.
1 megawatt (1 MW) equals 1,000 kW, the kind of rating used for wind turbines and medium-scale solar farms.
A 1.5 horsepower water pump motor draws about 1,119 W — useful for sizing a generator or UPS.
An iPhone wall charger is rated about 20 W; a laptop charger 65–100 W; a microwave oven 1,000 W.
The Tesla Model S Plaid delivers up to 1,020 horsepower (about 760 kW) — equivalent to the power of over a thousand home microwaves running at once.