Get our free calculator app, so it's always handy, or our Gear Recommender App!

So Dialed RC Setup App on the App StoreSo Dialed RC Setup App on the App Store

5 Stars on the App Store

Ian C.
Something every racer should have
Zaulu B.
Good app - it really lets you see what you are doing when pairing your gears. I would recommend it for anybody trying to hit high speed.
Cody B.
Helped me get a perfect top out speed and keep good temps.
Michael D.
Life saver...awesome app that helps tremendously.
William W.
This app is a big help to me to actually know and see what my drag car is doing. Very useful app, highly recommend it to anyone who drag races.
Cole M.
Great little tool, get their other app too, called "SO DIALED" its a lifesaver for tuning!
Billy J
This app is so helpful. It's a great tool to get your RC where you would like it to be.
Heath M.
It has changed me as a human, made me care a little more about humanity and the fellow creatures on this Earth. It's also a great R/C gear calculator.
Bryan T.
Excellent app for all tuning needs

Online Gear Ratio Calculator

Use our gear ratio and rollout calculator to find the right pinion and spur for your car, whether it's Team Associated, Tamiya, Traxxas, or any other make, . Enter your car's internal drive ratio to see the final drive ratio (FDR), and see the percentage change in gearing you'll get from a new pinion and spur.

Gears & Ratios

Enter your gearing to see the how your ratio will change.
Ratio
1
1
Ratio change
0%
Internal ratio
(Optional)
FDR
1
1
Rear tire diameter (Optional, for rollout)
Rollout
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Get our free Gear Calculator App (links above),
or try our
Gear Recommender App!

Change Impact Chart

Click/tap the gears to see how new gears will affect your ratio:
Pinion
Spur
13
0%
74
0%
14
0%
75
0%
15
0%
76
0%
16
0%
77
0%
17
0%
78
0%
18
0%
79
0%
19
0%
80
0%
20
0%
81
0%
21
0%
82
0%

Negative changes indicate a steeper ratio: higher top speed, but more strain on the motor/engine. Positive changes give more acceleration and put less strain on the motor/engine.