Electricity Unit Conversion (kW To HP) Calculator

Work out electricity unit conversion (kw to hp) instantly with clear inputs, formula shown and shareable results.

About Electricity Unit Conversion (kW To HP) Calculator

One mechanical horsepower is 745.6999 W and one metric horsepower (PS) is 735.49875 W, so the two differ by about 1.4%. Motor nameplates state shaft output, so applying efficiency gives the mechanical power actually delivered from a given electrical input.

Formula

Power conversion

1 hp = 745.6999 W; 1 PS = 735.49875 W; 1 kW = 3412.14 BTU/h

Worked example

With the default values below, Electricity Unit Conversion (kW To HP) Calculator returns Converted value of 10.0577. Change any input above and every figure here is recalculated in your browser.

Inputs used

Power: 7.5 kW
Motor efficiency: 90 %
Conversionone of kW to mechanical hp, Mechanical hp to kW: kW to mechanical hp

Results

Converted value: 10.0577
Equivalent metric horsepower: 10.20 PS
Shaft output allowing for efficiency: 6.75 kW
Equivalent heat rate: 25,591 BTU/h

Step by step

1Values used
2Power conversion
3Converted value= 10.0577
4Equivalent metric horsepower= 10.20 PS
5Shaft output allowing for efficiency= 6.75 kW
6Equivalent heat rate= 25,591 BTU/h

Assumptions and limits

The result is derived only from the 3 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 4 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
Electrical results are planning estimates only. Verify against the applicable wiring rules (IEC 60364, BS 7671, NEC or local code) and have all installation work designed and checked by a qualified electrician.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Electrical results are planning estimates only. Verify against the applicable wiring rules (IEC 60364, BS 7671, NEC or local code) and have all installation work designed and checked by a qualified electrician.

Frequently Asked Questions

Which horsepower is on my motor?

European and Asian motors usually state kW; US motors state mechanical hp. Automotive figures in Europe are often PS, which reads about 1.4% higher than hp.

Is electrical input the same as rated power?

No. Nameplate kW is shaft output, so electrical input is that divided by efficiency — a 7.5 kW motor at 90% draws about 8.3 kW.