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Horsepower Calculator

Calculate and convert different types of power measurements including mechanical, metric, electrical, and boiler horsepower with work, torque, and unit conversion methods.

Horsepower Calculator

Formulas Used

Power from Work: P = W/t = (F × d)/t

Where: P = Power, W = Work, F = Force, d = distance, t = time

Horsepower Definitions:

• Mechanical HP = 745.7 watts

• Metric HP (PS) = 735.5 watts

• Electrical HP = 746 watts

• Boiler HP = 9,809.5 watts

Horsepower Results

Horsepower Results

Mechanical HP:18.182
Metric HP (PS):18.434
Electrical HP:18.175
Boiler HP:1.382148

Other Power Units

Watts:13558.18
Kilowatts:13.558
BTU/hour:46262.44
ft-lb/sec:10000.00
cal/sec:3240.48

Work Done

Joules:135581.81
Foot-pounds:100000.00
BTU:128.5067
Calories:32404.83

Equivalent Torque at 3000 RPM

Newton-meters:43.16
Pound-feet:31.83
Kilogram-meters:4.40

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What is Horsepower Calculator?

Understanding Horsepower

Horsepower is a unit of power that measures the rate at which work is done. Originally defined by James Watt in the 18th century to compare steam engines with draft horses, it remains widely used in automotive, mechanical, and industrial applications.

Types of Horsepower

  • Mechanical HP: 745.7 watts - Original definition, most common
  • Metric HP (PS): 735.5 watts - Used in Europe and automotive industry
  • Electrical HP: 746 watts - Used for electric motors
  • Boiler HP: 9,809.5 watts - Used for steam boilers and large equipment

Calculation Methods

From Work:

Power = Work ÷ Time = (Force × Distance) ÷ Time

From Torque & RPM:

HP = (Torque × RPM) ÷ 5,252 (for lb-ft and mechanical HP)

P = Torque × Angular Velocity (for metric units)

Common Applications

  • Automotive: Engine power rating, performance comparison
  • Industrial: Motor sizing, pump and compressor specifications
  • Marine: Boat engine power, propulsion systems
  • Agricultural: Tractor and equipment power ratings
  • HVAC: Fan and compressor motor specifications

Power vs Torque

  • Torque: Rotational force - determines pulling power and acceleration
  • Power: Rate of doing work - determines how quickly torque can be applied
  • Relationship: Power = Torque × Angular Speed
  • Peak Power: Usually occurs at higher RPM than peak torque


FAQ - Horsepower Calculator

Mechanical horsepower (745.7 watts) is the original definition used in the US and UK. Metric horsepower or PS (735.5 watts) is about 1.4% smaller and is commonly used in Europe and the automotive industry. Always check which type is being used when comparing power ratings.