Free Tool

Motorcycle Tire
Size Calculator

Enter any tire size to see full specs — diameter, circumference, revolutions per mile. Compare two tires side-by-side to check fitment and speedometer implications.

Format: Width/Aspect Ratio RimDiameter  Examples: 120/70ZR17  ·  180/55ZR17  ·  90/90-21
Results for
Section Width
Aspect Ratio
Sidewall as % of width
Rim Diameter
Sidewall Height
Overall Diameter
Circumference
Revs Per Mile
At rated pressure

Speed Rating