HP to Torque Calculator
Easily convert horsepower to torque using our hp to torque calculator. Get accurate results in seconds for engines, motors, and mechanical systems. This guide helps you understand, calculate, and apply hp to torque conversions correctly.
Horsepower to Torque Converter
How to Use HP to Torque Calculator
Follow these simple steps to use the hp to torque calculator:
- 1Enter Horsepower (HP)
Input the horsepower value of your engine or motor. - 2Enter RPM (Revolutions Per Minute)
Provide the operating speed in RPM. Torque depends on speed. - 3Click Calculate
The calculator instantly converts HP to torque. - 4View Result
The result shows torque in lb-ft (or Nm depending on settings).
Tips:
- Always use accurate RPM values.
- Use consistent units (HP and RPM).
- Check if output is in lb-ft or Nm.
How to Convert HP to Torque
To convert horsepower to torque, you need to know the rotational speed (RPM). Use this standard formula:
Step-by-Step Example:
Given:
HP = 100
RPM = 2000
Step 1: Multiply HP by 5252
100 × 5252 = 525,200
Step 2: Divide by RPM
525,200 ÷ 2000 = 262.6 lb-ft
Final Answer:
Torque = 262.6 lb-ft
Key Notes:
- Higher RPM reduces torque for the same HP.
- Lower RPM increases torque.
- This formula works for mechanical systems and engines.
HP to Torque Conversion Chart (at 1800 RPM)
Note: Values depend on RPM. This chart assumes 1800 RPM.
| Horsepower (HP) | Torque (lb-ft) |
|---|---|
| 1 HP | 2.92 lb-ft |
| 5 HP | 14.6 lb-ft |
| 10 HP | 29.2 lb-ft |
| 20 HP | 58.4 lb-ft |
| 50 HP | 146.0 lb-ft |
| 75 HP | 219.0 lb-ft |
| 100 HP | 292.0 lb-ft |
| 150 HP | 438.0 lb-ft |
| 200 HP | 584.0 lb-ft |
| 300 HP | 876.0 lb-ft |
Unit Standardization: SI vs. Imperial Sizing in HP to Torque
When working with HP to Torque calculations, using consistent physical units is vital. Small translation errors between SI Metric units (like millimeters, kilowatts, and meters) and Imperial units (like AWG wire, horsepower, and feet) can lead to serious sizing errors:
| Dimension | SI Metric Unit | Imperial Unit | Conversion Conversion Factor |
|---|---|---|---|
| Power | Kilowatts (kW) | Horsepower (HP) | 1 kW ≈ 1.341 HP |
| Length | Meters (m) | Feet (ft) | 1 m ≈ 3.2808 ft |
| Flow Rate | Cubic meters/hr (m³/h) | Gallons/minute (GPM) | 1 m³/h ≈ 4.403 GPM |
Always perform unit checks before installing physical components for HP to Torque to ensure they match equipment specification sheets.
FAQs About HP to Torque Calculator
An HP to torque calculator is a mechanical engineering tool used to determine the rotational twisting force (torque) of an engine or motor based on its total power output in horsepower and operating speed in revolutions per minute (RPM).
Horsepower is a function of both torque and rotational speed. Because horsepower is defined as torque multiplied by RPM divided by a constant, you must know the rotational speed (RPM) to mathematically isolate and calculate the torque value.
The constant 5252 is a mathematical conversion factor derived from the definition of one horsepower (33,000 foot-pounds per minute) divided by 2π (representing the rotational path of one radian), which equates to approximately 5,252.11.
Yes, you can manually calculate torque by multiplying the motor's horsepower rating by the constant 5252, and then dividing the product by the shaft's rotational speed in RPM to obtain the final twisting force in pound-feet (lb-ft).
Yes. Since horsepower is a product of torque and speed, operating at a lower rotational speed (RPM) requires a higher twisting force (torque) to achieve or maintain the same total mechanical power output (horsepower) in the system.
This calculator supports both standard imperial units of pound-feet (lb-ft), which is commonly used in the United States, as well as metric Newton-meters (Nm), which is the standard torque unit throughout Europe and international engineering.