TORQUE • RPM • QUARTER-MILE • KW

Horsepower Calculator

Calculate engine horsepower from torque and RPM, estimate HP from quarter-mile times, and convert between HP, kW, PS, and watts.

4 METHODS5,252 HP CONSTANTHP↔kW CONVERTERP/W RATIO

Horsepower Calculator

Torque · Quarter-Mile · Converter

HP = (Torque × RPM) / 5,252

HORSEPOWER

299.9 HP

HP REFERENCE

Horsepower of Famous Vehicles

From economy cars to hypercars — HP, torque, and 0-60 mph times.

VehicleHPTorque (lb-ft)kW0-60 mph
Toyota Corolla (2024)169 HP151 lb-ft126 kW8.2 sec
Honda Civic Si (2024)200 HP192 lb-ft149 kW6.5 sec
Ford Mustang GT (2024)480 HP418 lb-ft358 kW4.2 sec
Chevrolet Camaro SS455 HP455 lb-ft339 kW4.0 sec
Tesla Model 3 Performance510 HP471 lb-ft380 kW3.1 sec
Dodge Challenger SRT Hellcat717 HP656 lb-ft535 kW3.6 sec
Lamborghini Huracán631 HP443 lb-ft470 kW3.2 sec
Ferrari SF90 Stradale986 HP590 lb-ft735 kW2.5 sec
Bugatti Chiron Super Sport1,578 HP1,180 lb-ft1,176 kW2.3 sec
Rimac Nevera (EV)1,914 HP1,740 lb-ft1,427 kW1.85 sec

🔁 Torque and HP Curves Always Cross at Exactly 5,252 RPM

This is a mathematical certainty from HP = (Torque × RPM) ÷ 5,252 — not a coincidence, it's pure algebra. Below 5,252 RPM, torque is numerically higher than HP; above it, HP is higher than torque, purely because of how the units and constant work out.

🌀 Torque vs Horsepower

Torque is the rotational force an engine exerts — measured in lb-ft or Nm — and determines how hard the engine pushes at any instant. High torque at low RPM is why trucks and diesels feel strong pulling away from a stop. Horsepower = Torque × RPM ÷ 5,252, so it accounts for how fast you're applying that torque. A sports car making 300 lb-ft at 7,000 RPM produces about 400 HP, while a diesel truck making 400 lb-ft at 2,000 RPM only makes about 152 HP. HP governs top speed and sustained power; torque governs pull and towing capacity.

⚖️ Power-to-Weight Ratio

Raw horsepower means little without knowing the vehicle's weight. A 300 HP sports car weighing 2,800 lbs (9.3 lbs/HP) accelerates far faster than a 400 HP SUV at 5,200 lbs (13 lbs/HP). Formula: lbs per HP = vehicle weight ÷ HP — lower is faster. Reference tiers: 1-2 lbs/HP supercars, 5-7 lbs/HP performance cars, 8-12 lbs/HP average sedans, 16-20 lbs/HP heavy trucks, 25-40 lbs/HP heavy trucks/vans.

How to Calculate Horsepower — All Methods

Horsepower can be calculated multiple ways depending on what data you have available — from a dynamometer reading of torque and RPM, from a quarter-mile timing slip, or directly from power measurements in watts or kilowatts. Each method gives a slightly different perspective on engine performance.

Method 1: From Torque and RPM (Dyno)

HP = (Torque[lb-ft] × RPM) / 5,252 Example: 350 lb-ft @ 4,500 RPM → HP = (350 × 4,500) / 5,252 ≈ 300 HP Metric: kW = (Torque[Nm] × RPM) / 9,549, then HP = kW / 0.7457

Method 2: Trap Speed (Quarter-Mile)

Wheel HP = Weight[lbs] × (Trap Speed[mph] / 234)³ Example: 3,200 lbs, 105 mph trap → HP = 3,200 × (105/234)³ ≈ 289 HP (at the wheels)

Method 3: Elapsed Time (ET)

Wheel HP = Weight[lbs] / (ET[sec] / 5.825)³ Example: 3,200 lbs, 13.5s ET → HP = 3,200 / (13.5/5.825)³ ≈ 257 HP (at the wheels)

Power Unit Conversions

1 HP = 745.7 W = 0.7457 kW = 1.0139 PS 1 kW = 1.341 HP = 1.3596 PS · 1 W = 1.341×10⁻³ HP 200 HP = 149.1 kW = 202.8 PS · 300 HP = 223.7 kW = 304.2 PS · 500 HP = 372.9 kW = 506.9 PS

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