Rolling Resistance Power Calculator

About this calculator

Rolling resistance is the force that resists a wheel's motion as its contact patch continuously deforms and recovers against the road or ground, calculated as F = Crr × m × g, where Crr is the rolling resistance coefficient (a dimensionless value that depends on tire construction, pressure, and surface — asphalt, gravel, or a treadmill belt). Multiplying that force by speed gives the power being spent purely to overcome rolling resistance, separate from the power lost to aerodynamic drag or gained/lost to gradient.

This calculator takes mass, speed and a rolling resistance coefficient and returns both the resistance force and the power it costs to overcome. Cyclists and triathletes comparing tire choices, bike fitters and coaches building power-based training models, and mechanical engineers estimating vehicle drivetrain losses use it to isolate exactly how many watts a given tire or surface is costing at a target speed, which is one of the few variables a rider can meaningfully control alongside aerodynamics.