Tyre sizes·255/65R17
255/65R17
Overall diameter 763.3 mm

255/65R17 — 763.3 mm tall, and what it swaps with

255/65R17 is 255 mm wide with a 65% sidewall on a 17-inch wheel. That sidewall is 165.75 mm, so the tyre stands 763.3 mm tall and turns 417 times per kilometre.

Section width
255 mm
Aspect ratio
65 %
Wheel size
17 in (431.8 mm)
Sidewall height
165.75 mm
Overall diameter
763.3 mm (30.05 in)
Circumference
2398 mm
Turns per km
417

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 255/65R17?

763.3 mm — the 431.8 mm wheel plus the 165.75 mm sidewall at top and bottom.

Q. How many turns per kilometre does 255/65R17 make?

Its circumference is 2398 mm, so 417 turns.

Q. What can I swap it for?

12 sizes stay within 3% of its diameter — the closest is 255/60R18 at 763.2 mm.

Q. Why is the sidewall 165.75 mm?

Because it is 65% of the 255 mm width. The aspect ratio is a proportion of the width, not a length.