About Power Converter
Power Converter exchanges a power rating between five units: watts, kilowatts, megawatts, horsepower and BTU per hour. It is the tool for reading a specification written in one convention when you think in another — a car engine quoted in horsepower, an electric motor rated in kilowatts.
The watt-based units are decimal and exact: a kilowatt is a thousand watts and a megawatt is a million. Horsepower is the one to watch. The value used here is 745.7 watts, the mechanical or imperial horsepower, which is what vehicle specifications usually mean. Metric horsepower, sometimes written as PS or CV, is a different figure at about 735.5 watts, so a rating quoted in metric horsepower will convert about 1.4 percent low if you use this tool blindly.
The result is a plain number without a unit suffix, matching whichever unit you selected in the second list. Because power ratings range from a few watts for a phone charger to hundreds of megawatts for a power station, check the magnitude to confirm the units you chose.
Only five units are on offer, and the gaps are the ones that come up in practice. There is no metric horsepower among them, despite that being the variant much of the world quotes, so a rating given in PS or CV has to be adjusted by hand before it can be converted. Boiler horsepower, tons of refrigeration and the dBm used in radio work are absent as well, as is any electrical framing such as volt-amperes — reactive power and apparent power are different quantities that this page does not distinguish. There is no way to add a factor of your own, no working or formula shown to check the arithmetic against, and no combined output covering several units at once.
How to use Power Converter
- 1 Enter the power value to convert.
- 2 Choose the source unit, for example kilowatts.
- 3 Choose the target unit such as horsepower, then run the conversion.
Frequently asked questions
Which horsepower does this tool use?
The mechanical or imperial horsepower of 745.7 watts, which is the figure usually intended in vehicle specifications. Metric horsepower, written PS or CV, is about 735.5 watts, so results differ slightly if your source used that variant.
What is a BTU per hour?
A rate of energy flow used mainly for heating and cooling equipment, where one BTU per hour is about 0.293 watts. Air conditioners and furnaces are commonly rated in BTUs per hour rather than watts.
Is a megawatt a thousand kilowatts?
Yes. The watt and its multiples are purely decimal, so a kilowatt is 1000 watts and a megawatt is 1000 kilowatts, or a million watts. There is no rounding anywhere in the watt-based conversions.
Why is my result smaller than the input number?
Because you converted from a smaller unit to a larger one. Going from watts to kilowatts divides by a thousand, so the number shrinks while the physical quantity stays the same.
Free, online, and private
Free to use
Power Converter is completely free. There is no account to create, no login, and no hidden charge or usage limit.
Runs online in your browser
It is a free online tool that runs entirely in your browser. Nothing to download or install — open the page and start using it right away.
Your data stays private
All processing happens locally on your device. Your input is never uploaded, stored, or tracked, so it never leaves your browser.
How Power Converter behaves in detail
These are the specifics of this implementation — the exact ranges, defaults and fixed settings you are working with.
| Parameter | Value |
|---|---|
| Units covered | 5 — W, kW, MW, horsepower and BTU/hour |
| Conversion basis | watt |
| Horsepower value | 745.7 W — the mechanical, or imperial, definition |
| BTU/hour value | 0.293071 W, i.e. 1,055.06 J shared over 3,600 seconds |
| Result precision | 8 decimal places, from a starting Value of 1 |
| Default pair | kW → hp |
Compiled from the implementation of this tool and checked against it by itoolnet.
What Power Converter does not do
Knowing the edges of a tool saves more time than another list of its features. These are the cases where it will not do what you might expect.
- Horsepower is fixed at the mechanical value of 745.7 W. Metric horsepower — the PS figure used across continental Europe, at 735.49875 W — is about 10.2 W lower, and electric and boiler horsepower are different again, so a PS rating converts slightly low with nothing to say which horsepower was meant.
- The BTU here is the 1,055.06 J international-table value. The thermochemical BTU gives a marginally different watt figure, and two units that dominate real air-conditioning work — the refrigeration ton and kilocalories per hour — are missing from the list altogether.
- Only power appears. Energy, torque and rotational speed are separate quantities, so you cannot enter a torque and an rpm to get a wattage here; that multiplication has to be done before or after, and no efficiency factor can be applied.
Tested and documented by itoolnet, the team that builds and maintains this site.