SpecCalc Hub
kW to HP Converter: Mechanical Horsepower & Motor Examples
Convert kW to mechanical hp or hp to kW with one input. See 7.5 kW and 3050 kW examples, metric PS differences and motor nameplate limitations.
Enter the values
Client-side estimate. SpecCalc Hub does not store entered values.
Formula: hp = kW / 0.745699872
Reference formula
This simplified formula block is educational and depends on the page status and limitations.
hp = kW / 0.745699872
Assumptions
- Inputs are user-provided.
- The result is an informational estimate.
Limitations
- Uses mechanical horsepower.
What this page helps with
This converter uses mechanical horsepower: 1 hp = 0.745699872 kW. Enter only the known side for a single-direction result. When both boxes are filled, they are two independent conversions, not a consistency check between the boxes.
Convert power in either direction between kW and mechanical horsepower. Only the input for the direction you need is required.
kW and horsepower both describe power, but they are often used in different purchasing and maintenance contexts. Motor nameplates, pump catalogs and mechanical brochures may switch between them, so a clean conversion avoids mismatched comparisons.
Convert kilowatts to mechanical horsepower or back. Compare power at the same point in the system: a motor’s rated mechanical output is not its electrical input because conversion losses must also be considered.
Formula or method
Mechanical hp = kW / 0.745699872; kW = hp × 0.745699872. Metric horsepower (PS/CV) uses approximately 0.73549875 kW per unit and is a different convention; the interactive result remains mechanical hp. Supply voltage and phase count do not change the unit conversion.
SpecCalc Hub uses mechanical horsepower for the visible conversion: hp = kW / 0.745699872 and kW = hp x 0.745699872.
The result is a unit conversion. It does not decide motor input current, feeder size, overload settings, torque or efficiency.
How to use
- Enter the known value in kilowatts or horsepower and read the converted result on the same page.
- Treat the output as a unit conversion first, not as a full motor performance statement.
- If you are comparing motors, check whether the quoted value is shaft output power, electrical input power or a marketing rating.
Practical examples
A common question, worked through
7.5 kW is approximately 10.058 mechanical hp, but approximately 10.197 metric PS. A 3050 kW value is approximately 4090.117 mechanical hp. These are unit conversions, not recommended catalogue motor sizes.
Worked example with the form defaults
Example inputs: Kilowatts: 7.5 kW; Mechanical horsepower: 10 hp. hp = kW / 0.745699872. Calculated outputs: kW to hp: 10.058 hp; hp to kW: 7.457 kW.
Example 1: 7.5 kW motor comparison
A 7.5 kW rating converts to roughly 10.06 hp using mechanical horsepower. This is useful when one supplier lists kW and another lists hp for a similar machine.
Example 2: hp back to kW
If a datasheet shows 15 hp, the equivalent is about 11.19 kW. You still need efficiency and power-factor checks if you are estimating electrical input current.
Common conversion table
Useful checkpoints: 0.75 kW = 1.01 hp, 1.2 kW = 1.61 hp, 5 kW = 6.71 hp, 11 kW = 14.75 hp, 22 kW = 29.50 hp and 100 kW = 134.10 hp using mechanical horsepower.
Common mistakes
- Mixing shaft output power with electrical input power.
- Assuming horsepower alone is enough for current or breaker selection.
- Ignoring which horsepower convention is being used.
Limitations
- Do not confuse shaft output with electrical input. For a hypothetical 7.5 kW shaft load at 90% efficiency, electrical input is 8.333 kW; current additionally needs voltage, power factor and the correct phase model.
- Mechanical hp and metric PS/CV are different units. This tool uses 1 mechanical hp = 745.699872 W; do not relabel a metric horsepower value without conversion.
- This page converts units only; it does not estimate efficiency, torque or starting current.
- Mechanical and electrical ratings must still be verified from the equipment datasheet.
- Use motor current or motor power tools for broader electrical planning.
FAQ
Does 440 V three-phase change the kW-to-hp factor?
No. Those parameters matter when calculating current or input power, not when converting an already known power between units.
Is hp the same as metric horsepower or PS?
No. The two factors differ. Check the source’s convention before using a vehicle or motor rating; this form explicitly reports mechanical hp.
Is 1 hp always the same as 0.746 kW?
For mechanical horsepower, that is the usual engineering approximation. Some regions also mention metric horsepower, so the convention should be checked in the source document.
Can I size a feeder from hp alone?
No. You also need voltage, phase type, efficiency, power factor and local electrical rules.
Why do catalogs still use hp?
Because many motor, pump and engine markets still publish legacy mechanical ratings in horsepower.
How many HP is 1.2 kW?
Using mechanical horsepower, 1.2 kW is about 1.61 hp.
How many HP is 7.5 kW?
Using mechanical horsepower, 7.5 kW is about 10.06 hp.
What is the kW to HP formula?
For mechanical horsepower, hp = kW / 0.745699872. The reverse is kW = hp x 0.745699872.
Related tools
Explanation updated: 2026-09-16
This calculator provides an estimate for informational purposes only. It is not a certified engineering design, electrical safety approval, or professional installation recommendation. Always verify final decisions with a qualified professional and applicable local codes.