I got to thinking about what the golden ratio of tire diameter to width was (subjective, I know), so I started plugging some numbers into an Excel worksheet. Here’s what I have so far based on vehicles I’ve either owned or have an opinion on.

So far, I’m finding that, to my eye, if a tire’s width is less than about 32.5% of its height, it looks too narrow to me. Give me some other ones to plug in.

EDIT: I have to leave, so I’ll leave the formulas here for you guys to calculate on your own.

  1. Convert width in mm to inches: Section width / 25.4
  2. Sidewall height: Section width in inches * aspect ratio %
  3. Overall diameter: Wheel diameter + 2x sidewall height
  4. Width to Diameter percentage: Width / Overal Diameter