Tools:
Gear Ratio Calculator Model Scaler Bricksafe Thumbnails Brickshelf Thumbnails Wheels Chart Unit Converter
Now available as free Android app: Get it on Google Play
Calculator
Click the images to select the respective gears. Start with the first pair and add more pairs as needed:
8
12
12
14
16
16
16
20
20
20
24
24
24
16
24
28
28
36
40
28
56
56
60
140
168
1
8
12
12
14
16
16
16
20
20
20
24
24
24
16
24
28
28
36
40
28
56
56
60
140
168


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.

Red gear: teeth | Yellow gear: teeth

Gear coupler
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:

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