Home/Mathematics/Watts to Horsepower

Formula & Calculator

Watts to Horsepower

Converts a power value measured in watts into mechanical horsepower using the standard conversion factor.

MathematicsUnit ConversionDaily Life

Watts to Horsepower Calculatorhp = W · 0.00134102

hp = W × 0.00134102
hp = horsepower (mechanical)  ·  W = watts  ·  1 W = 0.00134102 hp
⟹ ConvertW, hp
W
hp
Convert:
Presets:
hp
W: hp:
✓ Copied!
Power Gauge
Low Medium High Very High
1 W = 0.00134102 hp  ·  hp = W × 0.00134102  ·  W = hp / 0.00134102

Interpretation

hp = W × 0.00134102. Converts power from watts to horsepower. Used in automotive and machinery.

hp = W * 0.00134102
Watts to Horsepower

Variables

SymbolQuantityUnit
hpPower in horsepower
WPower in watts

What it means

Horsepower (hp) is a unit of power commonly used for engines and motors. The conversion factor is 1 W = 0.00134102 hp (mechanical horsepower). It is used to compare engine outputs, to size motors, and in engineering specifications. This conversion is essential for mechanical engineers and automotive enthusiasts.

Worked example

Watts to Horsepower – Two Examples

Real‑World
Scenario: An electric motor is rated at 1000 W. Convert to hp.
ParameterValue
W1000
1hp = 1000 × 0.00134102 = 1.341 hp
Result 1.34 hp ✓ Motor
Scenario: A car engine produces 150,000 W. Convert to hp.
ParameterValue
W150,000
1hp = 150000 × 0.00134102 = 201.15 hp
Result 201.15 hp ✓ Car engine
Insight: 1 hp = 745.7 W. Multiply W by 0.001341 to get hp.

Common mistakes

  • Conversion factor: 1 W = 0.00134102 hp – multiply watts by this factor.
  • Direction: This converts W to horsepower (mechanical).
  • Horsepower variants: Mechanical hp (550 ft·lb/s) vs. metric hp – use the correct one.
  • Precision: Use appropriate decimal places.
  • Applications: Used in engines, motors, and mechanical systems.

Applications

Watts to horsepower conversion, hp = W × 0.00134102, is commonly used in automotive, industrial, and mechanical engineering to compare power outputs. Horsepower is a traditional unit for engine power, while watts are SI. Engineers use it for motor sizing, vehicle performance, and equipment specifications. By converting accurately, professionals can ensure that power ratings are understood and applied correctly, facilitating global trade and compliance with standards.

  • Engine and motor power rating comparisons
  • Automotive and vehicle performance specifications
  • Industrial equipment and machinery sizing
  • HVAC and pump system power calculations
  • Education and practical power unit conversion

Frequently Asked Questions

Q01What is the formula for converting watts to horsepower?
A01

The conversion is hp = W × 0.00134102. This uses the mechanical horsepower (745.7 W).

Q02What is the common mistake when using this formula?
A02

Using an overly rounded conversion factor, which introduces noticeable error for large power values.

Q03What is the exact conversion factor?
A03

1 hp = 745.699872 W. Therefore, 1 W = 0.00134102 hp.

Q04How do you convert 1000 W to hp?
A04

1000 × 0.00134102 = 1.34102 hp.

Q05What is the inverse conversion from hp to W?
A05

W = hp / 0.00134102 = hp × 745.7.

Q06What are the applications of this conversion?
A06

Engine power ratings, motor specifications.