Tyre sizes·225/45R17
225/45R17
Overall diameter 634.3 mm

225/45R17 — 634.3 mm tall, and what it swaps with

225/45R17 is 225 mm wide with a 45% sidewall on a 17-inch wheel. That sidewall is 101.25 mm, so the tyre stands 634.3 mm tall and turns 501.8 times per kilometre.

Section width
225 mm
Aspect ratio
45 %
Wheel size
17 in (431.8 mm)
Sidewall height
101.25 mm
Overall diameter
634.3 mm (24.97 in)
Circumference
1992.7 mm
Turns per km
501.8

Sizes you can swap to

Only sizes whose overall diameter stays within 3% are listed. A different diameter covers a different distance per turn, and that gap becomes speedometer error.

Same profile, different width

Other sizes for this wheel

How the code reads

The 205 is millimetres, the 55 is a percentage of that width, and only the 16 is inches. The R stands for radial construction.

How to read this

  • The first three digits are the width in mm, the middle two are the aspect ratio in percent, the last two the wheel in inches.
  • Sidewall height = width × aspect ÷ 100. For 205/55 that is 112.75 mm.
  • Overall diameter = wheel diameter + twice the sidewall. A 16-inch wheel is 406.4 mm.
  • Once the diameter shifts by more than 3%, the speedometer and odometer drift by the same amount.

Frequently asked questions

Q. What is the overall diameter of 225/45R17?

634.3 mm — the 431.8 mm wheel plus the 101.25 mm sidewall at top and bottom.

Q. How many turns per kilometre does 225/45R17 make?

Its circumference is 1992.7 mm, so 501.8 turns.

Q. What can I swap it for?

12 sizes stay within 3% of its diameter — the closest is 195/65R15 at 634.5 mm.

Q. Why is the sidewall 101.25 mm?

Because it is 45% of the 225 mm width. The aspect ratio is a proportion of the width, not a length.