Torque to HP Calculator
Calculate horsepower from torque and RPM using the fundamental power equation for automotive and engineering applications
Power Calculator
300 lb-ft @ 5000 RPM = 285.7 HP Mechanical HP
285.7 HP @ 5000 RPM = 300 lb-ft lb-ft
Power Curve Relationship
Power = Torque × Angular Velocity. Peak torque typically occurs at lower RPM, while peak power occurs at higher RPM.
Related Power Calculators
Torque to HP Calculator - Understanding Power and Torque
The Torque to HP Calculator uses the fundamental relationship between torque, rotational speed (RPM), and power to calculate horsepower. This relationship is essential for understanding engine performance, motor sizing, and mechanical system design.
The Power Equation
The relationship between torque and horsepower is defined by the equation:
- For lb-ft: HP = (Torque × RPM) ÷ 5,252
- For Nm: HP = (Torque × RPM) ÷ 7,121
- Where: 5,252 and 7,121 are conversion constants
Understanding Torque vs. Horsepower
Torque and horsepower measure different aspects of rotational power:
- Torque: Measures rotational force or "twisting power" - how much force is applied
- Horsepower: Measures the rate of work - how quickly that force is applied
- RPM: The speed at which the rotation occurs
- Relationship: Power increases linearly with both torque and RPM
How to Use This Calculator
Converting between torque and horsepower requires RPM:
- Step 1: Select your preferred torque unit (lb-ft, Nm, etc.)
- Step 2: Choose calculation direction (Torque→HP or HP→Torque)
- Step 3: Enter torque and RPM values (or HP and RPM)
- Step 4: Click calculate to see the result with the mathematical formula
Real-World Applications
This calculator is essential for various applications:
- Automotive: Understanding engine power curves and performance characteristics
- Electric Motors: Sizing motors for specific torque and speed requirements
- Industrial Equipment: Calculating power requirements for machinery
- Engineering Design: Optimizing gear ratios and power transmission systems
Torque and Power Comparison Chart
See how different torque values convert to horsepower at various RPM levels:
| Torque (lb-ft) | 2000 RPM | 4000 RPM | 6000 RPM | 8000 RPM |
|---|---|---|---|---|
| 100 lb-ft | 38.1 HP | 76.2 HP | 114.3 HP | 152.4 HP |
| 200 lb-ft | 76.2 HP | 152.4 HP | 228.6 HP | 304.8 HP |
| 300 lb-ft | 114.3 HP | 228.6 HP | 342.9 HP | 457.1 HP |
| 400 lb-ft | 152.4 HP | 304.8 HP | 457.1 HP | 609.5 HP |
| 500 lb-ft | 190.5 HP | 381.0 HP | 571.4 HP | 761.9 HP |
| 600 lb-ft | 228.6 HP | 457.1 HP | 685.7 HP | 914.3 HP |
| 800 lb-ft | 304.8 HP | 609.5 HP | 914.3 HP | 1219.0 HP |
| 1000 lb-ft | 381.0 HP | 761.9 HP | 1142.9 HP | 1523.8 HP |