Enter your chainring teeth, sprocket teeth, and wheel diameter into the calculator to determine your gear ratio.

Gear Ratio Calculation Formula

The following formula is used to calculate the gear ratio for your bike.

Gear Ratio = (Chainring Teeth / Sprocket Teeth) * (Wheel Diameter / 27)

Variables:

  • Gear Ratio is the ratio of the bike’s chainring to its sprocket.
  • Chainring Teeth is the number of teeth on the bike’s chainring.
  • Sprocket Teeth is the number of teeth on the bike’s sprocket.
  • Wheel Diameter is the diameter of the bike’s wheel in inches.

To calculate the gear ratio, divide the number of chainring teeth by the number of sprocket teeth, then multiply the result by the wheel diameter divided by 27.

What is Gear Ratio Calculation?

Gear ratio calculation refers to the process of determining the ratio between the number of teeth on the chainring and the sprocket. This ratio influences how easy or hard it is to pedal the bike, affecting the overall riding experience. A proper gear ratio ensures optimal performance and comfort during rides.

How to Calculate Gear Ratio?

The following steps outline how to calculate the gear ratio using the given formula.

  1. First, determine the number of teeth on your bike’s chainring and sprocket.
  2. Next, measure the diameter of your bike’s wheel in inches.
  3. Use the formula from above: Gear Ratio = (Chainring Teeth / Sprocket Teeth) * (Wheel Diameter / 27).
  4. Finally, calculate the gear ratio by plugging in the values.
  5. After inserting the variables and calculating the result, check your answer with the calculator above.

Example Problem:

Use the following variables as an example problem to test your knowledge.

Chainring Teeth = 42

Sprocket Teeth = 16

Wheel Diameter = 27 inches

FAQ

1. What is gear ratio?

Gear ratio is the ratio of the number of teeth on the chainring to the number of teeth on the sprocket. It determines how many times the wheel turns for each turn of the pedals.

2. How does gear ratio affect biking?

A higher gear ratio means harder pedaling but higher speed, while a lower gear ratio means easier pedaling but lower speed.

3. How often should I use the gear calculator?

It’s helpful to use the gear calculator whenever you make changes to your bike’s setup, such as replacing the chainring or sprocket.

4. Can this calculator be used for different bikes?

Yes, you can adjust the chainring teeth, sprocket teeth, and wheel diameter fields to match any bike to calculate the gear ratio accordingly.

5. Is the calculator accurate?

The calculator provides an estimate of your gear ratio based on the inputs provided. For exact figures, it’s best to measure the components directly.