Torque, RPM & power reference
See how power changes with shaft speed while holding the entered torque constant. Change an input to explore the relationship.
Input parameters
Set your values below. The table updates automatically.
Comparison results
This is a constant-torque comparison, not an engine dyno curve.
| Engine RPM | Torque (Nm) | Power (kW) | Power (hp) |
|---|---|---|---|
| 1,000 | 200 | 20.94 | 28.09 |
| 2,000 | 200 | 41.89 | 56.17 |
| 3,000 | 200 | 62.83 | 84.26 |
| 4,000 | 200 | 83.78 | 112.35 |
| 5,000 | 200 | 104.72 | 140.43 |
| 6,000 | 200 | 125.66 | 168.52 |
| 7,000 | 200 | 146.61 | 196.6 |
| 8,000 | 200 | 167.55 | 224.69 |
How this table is calculated
kW = torque(Nm) × RPM × 2π / 60000Rows use the same assumptions while varying the value in the first column. Input-unit controls change the units used to enter values; column headers always state the output units.
How to read this comparison
Torque is fixed at the entered value in every row, while shaft RPM changes. Power rises in direct proportion to RPM in this comparison. This isolates the formula rather than representing how a real engine torque curve changes.
A worked example with the initial inputs
At the initial 200 N·m and the 3,000 rpm row, power is 200 × 3,000 × 2π / 60,000 ≈ 62.832 kW. At 6,000 rpm with the same torque, power doubles to approximately 125.664 kW.
The live table changes when you edit its controls.
Use the interactive calculator to explore more scenarios, units and relevant inputs.
Frequently asked questions
Can I use peak engine torque for every RPM row?
That would create a constant-torque scenario, not a measured engine curve. To describe an actual engine, use torque measured at each corresponding RPM.
Why do input controls and column headers show different units?
The unit toggle changes how you enter dimensional inputs. Each output column keeps its stated unit so you can compare values consistently. Read the column header before copying a result.
Understand the method in more detail
Source and assumptions
Power and rate of work; mechanical horsepower conversion follows 550 ft·lbf/s.
NASA Glenn — What is power?Read the calculation methodology for model scope, unit conventions and review status.