This tool is aimed at all AFOLs. Use it to calculate final ratio of up to 10 pairs of gears, then select the desired type and number of motors to see the theoretical output (speed and torque). Includes 15 sizes of gear wheels and 26 various types of motors! Also included: a planetary ratio calculator, gear coupler for finding available gear combinations at given axle spacing and Gearcyclopaedia featuring detailed info on 38 types of gears. NEW: Combinations finder tab where you can enter a desired gear ratio and the numbers of pairs of gears you want to use, and the app will calculate the solution (exact or the closest possible).