RatioBench: Belt & Chain

Turn the pulleys, sprockets, belts, and chain lengths you already have into a short list of theoretical drive layouts. RatioBench works backward from driver RPM, target output RPM, and target shaft spacing. In Belt mode, enter available driver and driven effective diameters plus available effective belt lengths. In Chain mode, enter sprocket tooth counts, pitch, and optionally your stock even link counts. The app evaluates the combinations on your device and orders them by absolute output-speed error, then center-distance error. For each belt candidate, see: - calculated output RPM and ratio; - calculated center distance and both target errors; - ideal belt speed; and - theoretical wrap on the smaller pulley. For each chain candidate, see: - calculated output RPM and ratio; - calculated center distance and both target errors; - theoretical target pitches and the candidate's even link count; - sprocket pitch diameters; and - ideal chain speed. Review the input values and arithmetic behind the result instead of relying on an unexplained answer. Switch between inches and millimeters, enter inventories with a newline or semicolon, and compare bounded combinations entirely offline. No account, ads, analytics, tracking, subscription, or network connection is required. RatioBench is a theoretical geometry and ratio comparison tool. It does not calculate power or torque capacity, belt or chain tension, service factors, wear or life, lubrication, efficiency, shaft or bearing loads, alignment, guarding, component compatibility, or safe operating limits. Effective/pitch dimensions and the applicable manufacturer data must be identified correctly. Have the final equipment and installation reviewed by a qualified person.