Type a value, choose the units and get an instant answer. The table below the converter shows the same value in every power unit, and all factors use exact or internationally standard definitions.
How to convert power units
- Enter the value.
- Pick the unit to convert from and to (⇄ swaps them).
- Read the result, formula and the table of all units.
Power units
| Unit | Symbol | About |
|---|---|---|
| Watt | W | The SI unit of power: one joule per second. |
| Kilowatt | kW | 1,000 watts. Used for engines, solar systems and appliances. |
| Horsepower | hp | Mechanical (imperial) horsepower, about 745.7 W. |
| Metric horsepower | PS | Metric horsepower (PS), about 735.5 W, used by many car makers. |
| BTU per hour | BTU/h | Used for air-conditioner ratings. A “1 ton” AC is 12,000 BTU/h. |
| Ton (AC) | TR | Air-conditioning ton: 12,000 BTU/h or about 3.517 kW. |
Popular power conversions
HP to kW · kW to HP · Watts to HP · BTU to Ton · Ton to BTU · kW to BTU · PS to HP
Frequently asked questions
How accurate is the power converter?
It uses exact definitions where they exist and shows up to 10 significant figures, more than enough for everyday, school and engineering use.
Updated October 2026 · Built and tested by Sharjeel Tahir · How our tools are tested