Skip to main content
CalcChef

Power Converter

Convert mW, W, kW, MW, mechanical, metric (PS) and electric horsepower, BTU/h and refrigeration tons: 1 kW is 1.341 hp, 1 hp is 745.7 W. How it works

Use the Power Converter

Result
0.001 kW
From 1 W

1 Watts ≈ 0.001 Kilowatts

📱

A few watts

1.0 W, the scale of a phone charger

1mW1W1kW1MW1GW

All Conversions

Milliwatts1,000
Watts1.00
Kilowatts0.0010
Megawatts1.00e-6
Horsepower, mechanical0.0013
Horsepower, metric0.0014
Horsepower, electric0.0013
BTU/hour3.41
Refrigeration tons2.84e-4

About the Power Converter

1 kW = 1.34102209 hp = 3412.14163313 BTU/h, and 1 hp = 745.69987158 W. The power unit converter goes through watts to turn any of mW, W, kW, MW, mechanical, metric (PS) and electric horsepower, BTU per hour and refrigeration tons into the others, so a 200 kW electric motor reads as 268.20441792 hp.

Power conversions people look up

FromTo
1 kW1.34102209 hp
1 hp745.69987158 W
100 hp74.56998716 kW
300 hp223.70996147 kW
1 W3.41214163 BTU/h
1,000 BTU/h293.07107017 W
24,000 BTU/h7.03370568 kW
1 MW1341.0220896 hp
1 PS735.49875 W
1 PS0.98632007 hp
100 PS73.549875 kW
1 hp (electric)746 W

hp is mechanical horsepower unless marked, PS is metric horsepower and BTU is the International Table BTU, rounded to 8 decimals as the converter shows them.

Frequently asked questions

How many watts is 1 horsepower?
745.69987158 W for mechanical horsepower (550 ft·lbf/s). Metric horsepower (PS, CV or pk) is 735.49875 W, so 1 PS is 0.98632007 hp, and electric horsepower is exactly 746 W. All three are in the unit list: a 100 PS engine is 73.549875 kW, not 74.57. Boiler horsepower is in the Horsepower to kW Converter.
How do I convert watts to BTU per hour?
Multiply watts by 3.41214163, or divide BTU/h by it to get watts. A 5,000 BTU/h window air conditioner moves 1465.35535086 W of heat, which is not the same as the electricity it draws.
How many kW is a ton of cooling?
One ton of cooling is 12,000 BTU/h, 3.51685284 kW. A 2-ton unit is 24,000 BTU/h, 7.03370568 kW, and a 3-ton unit 36,000 BTU/h, 10.55055853 kW. Refrigeration tons (TR) is one of the units, so enter the tonnage and read kW or BTU/h directly.
Is kW the same as kWh?
No. kW is power, a rate; kWh is energy, 1 kW kept up for one hour. This converter handles power units only. To turn watts and hours of use into kWh, use the Kilowatt Hour Calculator.

Watts, kilowatts, horsepower and BTU/h

Use it to compare an engine rated in horsepower with a motor rated in kilowatts, an air conditioner rated in BTU per hour with a heat pump in kW, or a solar panel's watts with a household load. A 150 hp engine is 111.85498074 kW. A 12,000 BTU/h air conditioner, one ton of cooling, moves 3.51685284 kW of heat; that is not its electrical draw, which is the cooling divided by its coefficient of performance. A 1,500 W space heater gives out 5118.21244969 BTU/h. Air conditioners and chillers are also rated in refrigeration tons: pick Refrigeration tons (TR) and 1 TR converts to 12000 BTU/h or 3.51685284 kW.

The grid under the result shows the value in all nine units at once, and the preset chips fill typical ratings such as a 1,000 W microwave or a 50 kW industrial motor.

Factors and common mix-ups

Every conversion goes through watts: result = value × factor(from) ÷ factor(to).

  • mW = 0.001 W, kW = 1,000 W, MW = 1,000,000 W

  • hp (mechanical) = 745.69987158227 W (550 ft·lbf/s)

  • PS (metric horsepower) = 735.49875 W (75 kgf·m/s), so 1 PS = 0.98632007 hp

  • electric hp = 746 W exactly

  • BTU/h = 1,055.05585262 J ÷ 3,600 s ≈ 0.29307107 W

  • TR (ton of refrigeration) = 12,000 BTU/h = 3,516.8528420667 W

The main result is rounded to 8 decimal places, and values below 0.000001 switch to exponent form; the grid rounds to 2 decimals for most values. European and Japanese engine ratings are often in PS (also written CV or pk). Pick Horsepower, metric (PS) for them: entered as mechanical hp, a PS figure reads about 1.4% high, and 100 PS is 73.549875 kW, not 74.57.

Power is a rate. A kWh is energy, 1 kW sustained for an hour; BTU is energy and BTU/h is power. kVA is not here either: it is apparent power, and real power in kW is kVA × power factor.

Related Tools

View all tools
Conversion

Energy Converter

Convert J, kJ, cal, kcal, Wh, kWh, MWh, BTU, therms, ft·lbf, erg and eV either way: 1 kWh = 3.6 MJ = 860.42 kcal = 3412.14 BTU = 0.0341 therm.

Conversion

Pressure Unit Converter

Convert pressure between Pa, hPa, kPa, MPa, bar, psi, atm, Torr, mmHg, inHg and inH2O. 1 atm = 101,325 Pa = 14.6959 psi = 760 Torr.

Conversion

Speed Converter

Convert speed between mph, km/h, m/s, knots, ft/s and Mach (343 m/s): 60 mph is 96.56064 km/h, 26.8224 m/s and 88 ft/s.

Conversion

Torque Converter

Convert torque between N·m, lb·ft, lb·in and kgf·m. 1 N·m = 0.737562 lb·ft = 8.85075 lb·in, and 100 lb·ft = 135.582 N·m.

Conversion

Volume Converter

Convert liters, dL and cL, US and Imperial gallons, quarts, pints and fluid ounces, US cups and spoons, and cubic feet. 1 US gallon is 3.785411784 L.

Conversion

Acceleration Converter

Convert acceleration units like m/s², g-force, and ft/s². Physics and automotive engineering tool.