FREE UNIT CONVERTER
Power Converter
Fixpio’s power converter switches a rating between watts, kilowatts, mechanical horsepower, metric horsepower, BTU per hour and tons of refrigeration — the units printed on motors, car spec sheets, heaters and air conditioners. Type a value, pick your two units, and the answer updates as you type. It is a straightforward power unit converter that keeps mechanical horsepower (745.699872 W) and metric horsepower (735.49875 W) as separate choices, because they are not the same unit. Everything runs in your browser, so nothing you enter leaves your device.
- Updates instantly as you type
- Both horsepower definitions, kept separate
- Free, in-browser, no sign-up
Convert Power Units
Enter a rating, choose the unit it is in and the unit you want — the result appears straight away.
Formula: result = value × (from unit in watts / to unit in watts). For example, 1 kilowatt = 1000 / 745.699872 mechanical horsepower.
Horsepower is not one unit: mechanical hp = 745.699872 W, metric hp (PS) = 735.49875 W. Check which one your spec sheet uses — US/UK ratings are usually mechanical, European car figures are often PS.
Why power ratings never match across borders
The same machine gets a different number in every country. This page puts them on one scale.
Appliances in watts, sense in horsepower
A 1,500 W heater is about 2.01 mechanical horsepower; a 100 W bulb is 0.134 hp. Converting watts to horsepower makes old and new ratings comparable at a glance.
Cars and motors, honestly compared
Engine figures in hp, PS and kW differ by definition, not just rounding. Convert before you compare, and a 150 PS European model stops looking equal to a 150 hp one — it is about 147.9 hp.
Cooling without the confusion
Air conditioning is sold by the ton in the US and in BTU/h or kW elsewhere. One ton of refrigeration is exactly 12,000 BTU/h — about 3.517 kW of cooling capacity.
About this converter
Power is a rate: how fast energy is being used or delivered. The watt is its standard unit — one joule per second — and the kilowatt is simply 1,000 watts, which is why converting watts to kilowatts is just a decimal shift. The confusion starts with the older units that refuse to retire. This power converter handles the ones that still appear on real equipment: horsepower in its mechanical and metric forms, BTU per hour from the heating world, and tons of refrigeration from air conditioning, all converted through watts as the common base.
The numbers behind it are fixed. One mechanical horsepower is 745.699872 watts, so one kilowatt is about 1.341 mechanical horsepower; one metric horsepower is 735.49875 watts; one BTU per hour is about 0.293071 watts, making a kilowatt equal to about 3,412.14 BTU/h; and one ton of refrigeration is 3,516.85 watts. Whether you are checking a motor against its supply or turning kilowatts to horsepower for a spec sheet, those are the factors applied — instantly, in your browser.
Frequently asked questions
Straight answers about horsepower, kilowatts and cooling tons.
How do I convert horsepower to kilowatts?
Multiply mechanical horsepower by 0.745699872. A 150 hp engine is 150 × 0.745699872 = 111,854.98 W, about 111.85 kW. Going the other way, multiply kilowatts by about 1.34102: a 100 kW motor is roughly 134.1 hp.
What is the difference between mechanical and metric horsepower?
Mechanical horsepower — the US/UK unit — is 745.699872 W. Metric horsepower, labelled PS or CV on European spec sheets, is 735.49875 W, about 1.4% less. So 150 PS = 110,324.8 W ≈ 147.9 mechanical hp, not 150. This converter lists the two separately so you can pick the one your document uses. (A third figure, electrical horsepower at exactly 746 W, exists for US electric motors; it is close to mechanical hp but is not one of this tool’s units.)
How many watts are in 1 hp?
For mechanical horsepower, 745.699872 watts. That is why a 2,000 W appliance works out to about 2.68 hp, and why the rough ‘1 hp ≈ 746 W’ rule you will see quoted is a rounding of the mechanical figure.
How do I convert kW to BTU per hour?
Multiply by about 3,412.14: a 5 kW electric heater delivers about 17,061 BTU/h of heat. In reverse, divide BTU/h by 3,412.14 (equivalently, multiply by 0.293071 to get watts) — a 12,000 BTU/h air conditioner is moving about 3,516.85 W of heat.
What is a ton of refrigeration in kW?
One ton of refrigeration is a cooling capacity of 12,000 BTU/h, which is 3.51685 kW (3,516.85 W). A common 2-ton home system is therefore 24,000 BTU/h, about 7.03 kW of cooling. Note this is the cooling capacity — the heat the system removes — not the electrical power it draws, which is lower.
Is horsepower a unit of power or of energy?
Power. Horsepower, watts and BTU per hour all describe a rate — how fast work is done or heat is moved. Energy is the total: kilowatt-hours, joules and BTU. If you multiply a power rating by the hours it runs, you get energy — a 2 kW heater running for 3 hours uses 6 kWh. Use Fixpio’s Energy Converter for totals like that.