TORQDEX // TIRE-01

Tire Size Calculator

Compare two tire sizes and see how changes in width, aspect ratio, and wheel diameter affect overall size and speedometer accuracy.

CURRENT TIRE

mm
%
in

NEW TIRE

mm
%
in

CURRENT TIRE RESULT

TIRE SIZE ---
SIDEWALL HEIGHT -- in
OVERALL DIAMETER -- in
CIRCUMFERENCE -- in
REVOLUTIONS / MILE --

NEW TIRE RESULT

TIRE SIZE ---
SIDEWALL HEIGHT -- in
OVERALL DIAMETER -- in
CIRCUMFERENCE -- in
REVOLUTIONS / MILE --

COMPARISON

DIAMETER CHANGE -- %
RIDE HEIGHT CHANGE -- in
ACTUAL SPEED AT 60 MPH INDICATED -- MPH
SIZE DIFFERENCE WAITING FOR DATA

Enter both tire sizes to compare them.

01 // HOW TIRE SIZE WORKS

Reading a tire size

Width

In a size such as 225/45R17, the first number is the nominal tire width in millimeters.

Aspect ratio

The second number is the sidewall height as a percentage of tire width. A 45-series tire has a sidewall height approximately 45% of its nominal width.

Wheel diameter

The final number is the wheel diameter in inches. Overall tire diameter combines the wheel diameter with both tire sidewalls.

FORMULA

Overall tire diameter

Diameter = Wheel Diameter + (2 × Sidewall Height)

Sidewall height is calculated from tire width × aspect ratio, then converted from millimeters to inches.