Select your drive motor to see the theoretical output speed in RPM (Rotations Per Minute):
Ratio calculator for planetary gears
Assuming that the red gear is the input, the gray beam is the output and that the yellow gear is not rotating (e.g. fixed to a motor):
specify numbers of teeth for red and yellow gear below, then click calculate.
The red dot marks the position of your driver gear's axle. Select the position of your follower gear's axle to see the available gear combinations: