Select your product to confirm this information applies to you

Setting the Bike Wheel Size on a Garmin Fitness Device

Your bike's wheel size is automatically calculated over time when a Speed Sensor 2 or similar sensor is connected to a fitness device and used outdoors. In certain circumstances, such as when doing an indoor activity or when speed and distance readings are inaccurate, wheel size can be entered manually for improved accuracy on devices that allow this function. If you know your wheel size, select your device below and follow the steps to enter this measurement.

NOTE: Sensors have to be actively connected to the device to manually enter wheel size


Tire and Wheel Size Information

The tire size is marked on both sides of the tire and can be used to determine the circumference of the wheel in millimeters (mm). This is not a comprehensive list. You can also measure the circumference of your wheel or use one of the many calculators available on the internet.
Tire SizeWheel Circumference (mm)
20 × 1.751515
20 × 1-3/81615
22 × 1-3/81770
22 × 1-1/21785
24 × 11753
24 × 3/4 Tubular1785
24 × 1-1/81795
24 × 1.751890
24 × 1-1/41905
24 × 2.001925
24 × 2.1251965
26 × 7/81920
26 × 1-1.01913
26 × 11952
26 × 1.251953
26 × 1-1/81970
26 × 1.402005
26 × 1.502010
26 × 1.752023
26 × 1.952050
26 × 2.002055
26 × 1-3/82068
26 × 2.102068
26 × 2.1252070
26 × 2.352083
26 × 1-1/22100
26 × 3.002170
27 × 12145
27 × 1-1/82155
27 × 1-1/42161
27 × 1-3/82169
29 x 2.12288
29 x 2.22298
29 x 2.32326
650 x 20C1938
650 x 23C1944
650 × 35A2090
650 × 38B2105
650 × 38A2125
700 × 18C2070
700 × 19C2080
700 × 20C2086
700 × 23C2096
700 × 25C2105
700C Tubular2130
700 × 28C2136
700 × 30C2146
700 × 32C2155
700 × 35C2168
700 × 38C2180
700 × 40C2200
700 × 44C2235
700 × 45C2242
700 × 47C2268

Forerunner® Watches:

Select your model below for details:


Forerunner 230 | Forerunner 235 | Forerunner 630 | Forerunner 735XT

  1. If locked, unlock the screen.

  2. Press the Run key (top right).

  3. Navigate to Menu or select:

    • Forerunner 630: select3 lines.

  4. Select Settings.

  5. Select Sensors and Accessories.

  6. Select Speed sensor.

  7. Select Wheel Size.

  8. Select Manual.

  9. Enter in Wheel Size in millimeters (mm).


Forerunner 920XT

  1. Press Shortcut key (three dots on bottom left).

  2. Press ENTER to unlock screen.

  3. Press Shortcut key.

  4. Select Settings.

  5. Select Sensors and Accessories.

  6. Select Spd/Cad or Spd.

  7. Select Wheel Size.

  8. Select Manual.

  9. Enter in Wheel Size in millimeters (mm).


Forerunner 165 Series , 245 Series, 255 Series, 265 Series, 645 Series, 745, 935, 945, 945 LTE, 955, 955 Solar and 965

  1. Press and hold the Up/Menu Key.

  2. Access the settings option on the watch.

  3. Select Sensors & Accessories.

  4. Choose your previously paired speed sensor.

  5. Select Wheel Size.

  6. Select Manual.

  7. Enter in Wheel Size in millimeters (mm).



Edge® Cycling Computers

Edge 130 Series, 520 Series, 530, 540 Series, 820, 830, 840 Series, 1000, 1030 Series, 1040 Series, 1050 and Explore Series

  1. Select Menu or 3 lines.
  2. Select Settings (some devices skip this step).

  3. Select Sensors.

  4. Select the previously paired speed sensor.

  5. Select Sensor Details.

  6. Select Wheel Size.

  7. Select Manual.

  8. Enter in wheel size in millimeters (mm).


Other Garmin Watches

The following instructions should work for most Garmin watches: 

  1. Press and hold MENU.

  2. Select or scroll to Settings

  3. Select Sensors & Accessories.

  4. Select Speed Sensor (Spd. -xxxxxxx).

  5. Select Wheel Size.

  6. Select Manual.

  7. Enter Wheel Size in millimeters (mm).


Speed Sensor 2 via the Garmin Connect App

  1. Open the Garmin Connect app.

  2. Access the menu by selecting More (bottom right).

  3. Select Garmin Devices.

  4. Select Speed Sensor 2.

  5. Select General Settings.

  6. Select Wheel Size.

  7. Enter in Wheel Size in millimeters (mm).


For all other fitness devices, refer to your owner's manual.