Weight-to-Power Ratio Calculator

Performance metric from vehicle weight and HP.

Vehicle weight (lbs)

Horsepower (HP)

Torque (lb-ft)

Drivetrain loss (%)

Tab to move between fields

Lbs per HP

Lbs per WHP

16.47

HP per ton142.9

Watts per kg117.4

Est. 0-60 mph (sec)2.47

Est. 1/4-mile ET (sec)14.82

Torque per ton (lb-ft)136

Wheel HP212.5

Whp Per Ton121.43

Perf ClassStandard Sedan

How to Use This Calculator

How the result changes with Horsepower (HP)

Vehicle weight (lbs): Curb weight of the vehicle in pounds.
Horsepower (HP): Rated flywheel (crank) horsepower.
Torque (lb-ft): Peak torque in pound-feet.
Drivetrain loss (%): Percentage lost through transmission and differential (15% manual, 18% auto).

Lbs per HP: Lower is faster — weight divided by crank horsepower.
Lbs per WHP: Weight divided by wheel horsepower (after drivetrain loss).
HP per ton: Crank horsepower per short ton (2,000 lbs).
Watts per kg: International power-to-weight metric.
Est. 0-60 mph (sec): Estimated 0-60 time using modified Csere correlation.
Est. 1/4-mile ET (sec): Quarter-mile elapsed time from Huntington formula.
Torque per ton (lb-ft): Wheel torque per short ton — correlates with acceleration feel.
Wheel HP: Horsepower at the wheels after drivetrain loss.

Identify Input Parameters
4 parameters
Vehicle weight (lbs) = 3500, Horsepower (HP) = 250, Torque (lb-ft) = 280, Drivetrain loss (%) = 15 = 4 input(s) provided
Calculate Lbs per HP
Lbs per HP = vehicleWeight / max(1, horsepower)
14 = 14
Calculate Lbs per WHP
Lbs per WHP = vehicleWeight / max(1, whp)
16.47 = 16.47
Calculate HP per ton
HP per ton = (horsepower / vehicleWeight) * 2000
142.9 = 142.9
Calculate Watts per kg
Watts per kg = powerWatts / max(1, weightKg)
117.4 = 117.4