Tyre sizes·235/40R19
235/40R19
Overall diameter 670.6 mm

235/40R19 — 670.6 mm tall, and what it swaps with

235/40R19 is 235 mm wide with a 40% sidewall on a 19-inch wheel. That sidewall is 94 mm, so the tyre stands 670.6 mm tall and turns 474.7 times per kilometre.

Section width
235 mm
Aspect ratio
40 %
Wheel size
19 in (482.6 mm)
Sidewall height
94 mm
Overall diameter
670.6 mm (26.4 in)
Circumference
2106.8 mm
Turns per km
474.7

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 235/40R19?

670.6 mm — the 482.6 mm wheel plus the 94 mm sidewall at top and bottom.

Q. How many turns per kilometre does 235/40R19 make?

Its circumference is 2106.8 mm, so 474.7 turns.

Q. What can I swap it for?

12 sizes stay within 3% of its diameter — the closest is 215/50R18 at 672.2 mm.

Q. Why is the sidewall 94 mm?

Because it is 40% of the 235 mm width. The aspect ratio is a proportion of the width, not a length.