1 kilowatt is equal to 1.341022 mechanical horsepower (HP) and 1.35962 metric horsepower (PS).

How do you convert HP to kW?

To convert mechanical horsepower to kilowatts, divide by 1.341022: kW = HP(mech) ÷ 1.341022. For metric horsepower, use kW = HP(metric) ÷ 1.35962.

What is the difference between mechanical HP and metric HP?

Mechanical horsepower (also called imperial or SAE horsepower) is defined as 745.699872 watts. Metric horsepower (PS, CV, or hk) is defined as 735.49875 watts. As a result, 1 metric HP is about 1.4% smaller than 1 mechanical HP.

Which horsepower should I use for cars and electric motors?

In North America, car and motor ratings usually use mechanical horsepower. In many European documents you may see metric horsepower (PS or CV). Electric motors are often rated in kW first, with HP as a secondary value based on mechanical horsepower.

kW to HP Converter – Kilowatts to Horsepower (Mechanical & Metric)

Q: How do you convert kW to HP?

To convert kilowatts (kW) to mechanical horsepower (HP), multiply the power in kW by 1.341022. Formula: HP(mech) = kW × 1.341022. For metric horsepower, use HP(metric) = kW × 1.35962.

How to convert kW to HP

Kilowatts (kW) are the SI unit of power, while horsepower (HP) is a traditional unit still widely used for engines and electric motors. There are two common definitions of horsepower:

Mechanical horsepower (imperial, SAE): \(1\ \text{HP} = 745.699872\ \text{W}\)
Metric horsepower (PS, CV, hk): \(1\ \text{HP} = 735.49875\ \text{W}\)

Formulas:

Mechanical horsepower:

\[ \text{HP}_\text{mech} = \text{kW} \times 1.341022 \]

Metric horsepower:

\[ \text{HP}_\text{metric} = \text{kW} \times 1.35962 \]

Converting HP back to kW

To go from horsepower to kilowatts, invert the factors:

Mechanical horsepower to kW:

\[ \text{kW} = \frac{\text{HP}_\text{mech}}{1.341022} \]

Metric horsepower to kW:

\[ \text{kW} = \frac{\text{HP}_\text{metric}}{1.35962} \]

Worked examples

Example 1 – 100 kW to HP (mechanical)

\[ \text{HP}_\text{mech} = 100\ \text{kW} \times 1.341022 = 134.1022\ \text{HP} \] Rounded to two decimals: \[ 100\ \text{kW} \approx 134.10\ \text{HP (mechanical)} \]

Example 2 – 75 kW to HP (metric)

\[ \text{HP}_\text{metric} = 75\ \text{kW} \times 1.35962 = 101.9715\ \text{HP} \] So: \[ 75\ \text{kW} \approx 101.97\ \text{HP (metric)} \]

Example 3 – 200 HP to kW (mechanical)

\[ \text{kW} = \frac{200\ \text{HP}}{1.341022} \approx 149.14\ \text{kW} \]

Mechanical vs metric horsepower

The difference between mechanical and metric horsepower is small (about 1.4%), but it matters for precise engineering work:

Mechanical HP is standard in North America and many English-language datasheets.
Metric HP (PS, CV) is common in European automotive specs and older documentation.

For most car and motor comparisons, mechanical horsepower is the safest default unless the spec explicitly says “PS” or “CV”.

Typical kW and HP ratings

Small household pump: 0.37–0.75 kW ≈ 0.5–1 HP
Common single-phase motor: 1.5–3 kW ≈ 2–4 HP
Passenger car engine: 75–150 kW ≈ 100–200 HP
Heavy truck engine: 220–370 kW ≈ 300–500 HP

FAQ

How do you convert kW to HP?

Multiply kilowatts by 1.341022 for mechanical horsepower, or by 1.35962 for metric horsepower. Our calculator does this instantly and also supports the reverse HP → kW conversion.

What is 1 kW in HP?

1 kW ≈ 1.3410 HP (mechanical)
1 kW ≈ 1.3596 HP (metric)

Which unit should I use for electric motors?

Electric motors are normally rated in kW as the primary unit. If you need HP, convert using mechanical horsepower unless the manufacturer specifies otherwise.

kW to HP Converter (and HP to kW)

Kilowatts ⇄ Horsepower Calculator

kW to HP Conversion Table