HP / Torque Calculator
Convert between horsepower and torque at any RPM using the universal formula: HP = (TQ × RPM) ÷ 5252.
HP
381
lb-ft @ 5,000 RPM
400
Known Engines
HP at 400 lb-ft Across RPM Range
| RPM | HP |
|---|---|
| 2,000 | 152 |
| 2,500 | 190 |
| 3,000 | 228 |
| 3,500 | 267 |
| 4,000 | 305 |
| 4,500 | 343 |
| 5,000 | 381 |
| 5,252 ★ | 400 |
| 5,500 | 419 |
| 6,000 | 457 |
| 6,500 | 495 |
| 7,000 | 533 |
The 5252 Rule
• HP = TQ × RPM ÷ 5252. The constant 5252 comes from converting RPM to radians/minute (33,000 ÷ 2π ≈ 5252).
• HP and TQ curves on a dyno graph always cross at exactly 5252 RPM — it's a math identity, not an engine characteristic.
• Below 5252 RPM: torque number > HP number. Above 5252: HP number > torque number.
• Dyno figures are at the flywheel unless stated "at the wheels." Drivetrain loss is typically 12–18% for RWD, 10–15% for FWD.