BikeCalc

BikeCalc gets a redesign and a new app for its 15th year anniversary! Access the old table here.

Parameters

Chainring
50
Sprocket
15
25 mm
622 mm

Similar Gear Inches

(x: Chainring, y: Sprocket)

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Instructions

Learn how to use the original and most popular gear inches calculator for cyclists

The following instructions aim to assist you in effectively using our gear inches calculator, ensuring a more seamless and informed experience.

  1. Count the number of teeth on the front cog of your bicycle, and select this value in the picker labeled chainring.
  2. Do the same on your rear cog for the picker labeled sprocket.
  3. Measure in millimeters the thickness of your rear tire across its tread when inflated, and select this value in the picker labeled tire thickness.
  4. Do the same with the diameter of your rim up to its bead for the picker labeled rim diameter. Sometimes, a marking can also be found printed on the sidewall of the tire. If you're measuring in inches, please refer to our article explaining how to convert tire sizes to the international standard (ISO 5775).

For more information about gear inches, please visit our article answering common questions from the community.