Motorcycle Tire Size Converter

Find equivalent tire sizes based on overall diameter. Works with metric (120/70-17) and inch (3.50-18) formats.

Try:
Tolerance:overall diameter
Supported inch sizes (31)

How equivalency is calculated

Two tires are considered equivalent when they share the same rim diameter and their overall tire diameter is within the selected tolerance (default ±3%).

Section Height = Width × (Aspect / 100)
Overall Diameter = (Rim × 25.4mm) + (2 × Section Height)

Always verify with your bike's manual and a qualified mechanic before swapping tire sizes. Clearance, speedometer calibration, and handling can be affected.