Tyre sizes·265/35R21
265/35R21
Overall diameter 718.9 mm

265/35R21 — 718.9 mm tall, and what it swaps with

265/35R21 is 265 mm wide with a 35% sidewall on a 21-inch wheel. That sidewall is 92.75 mm, so the tyre stands 718.9 mm tall and turns 442.8 times per kilometre.

Section width
265 mm
Aspect ratio
35 %
Wheel size
21 in (533.4 mm)
Sidewall height
92.75 mm
Overall diameter
718.9 mm (28.3 in)
Circumference
2258.5 mm
Turns per km
442.8

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 265/35R21?

718.9 mm — the 533.4 mm wheel plus the 92.75 mm sidewall at top and bottom.

Q. How many turns per kilometre does 265/35R21 make?

Its circumference is 2258.5 mm, so 442.8 turns.

Q. What can I swap it for?

12 sizes stay within 3% of its diameter — the closest is 235/45R20 at 719.5 mm.

Q. Why is the sidewall 92.75 mm?

Because it is 35% of the 265 mm width. The aspect ratio is a proportion of the width, not a length.