Power converter
P = E / t
Convert a power between microwatts, milliwatts, watts, kilowatts, megawatts, gigawatts, metric horsepower, mechanical horsepower and BTU per hour. Metric and imperial horsepower are two different units commonly rendered by the same word: this tool distinguishes them and says so.
1 Metric horsepower (ch) = 0.73549875 Kilowatt (kW)
Raw value: 0.735499
Scientific dossier
What the tool computes, what it assumes, where it stops being valid, and where its data comes from.
Method & formulasP = E / t
P = E / t
1 ch = 735.49875 W (exactly)
1 hp = 745.69987 W (exactly)
Power is energy per unit time. Both “horsepower” definitions above are exact but do not denote the same quantity: metric horsepower is 75 kgf·m/s, imperial horsepower 550 ft·lbf/s.
- µW
- · Microwatt (µW)
- mW
- · Milliwatt (mW)
- W
- · Watt (W)
- kW
- · Kilowatt (kW)
- MW
- · Megawatt (MW)
- GW
- · Gigawatt (GW)
- ch
- · Metric horsepower (ch)
- hp
- · Mechanical horsepower (hp)
- BTU/h
- · BTU per hour (BTU/h)
- ch
- · Metric horsepower : 75 kgf·m/s = 735.49875 W. The imperial horsepower (hp) is 745.7 W, about 1.4 % higher. Both are commonly called “horsepower”.
- hp
- · Imperial mechanical horsepower: 550 ft·lbf/s = 745.69987 W. Not to be confused with metric horsepower (735.5 W).
- BTU/h
- · Derived from the international-table BTU, see the BTU note in the Energy dimension.
Validity domainA power quoted as 100 hp is 73.
A power quoted as 100 hp is 73.5 kW under the metric convention and 74.6 kW under the imperial one: the 1.4 % gap far exceeds usual display precision. European documentation generally uses metric horsepower, North American documentation the imperial one. When the source does not say, the ambiguity is real and no conversion can resolve it.