Tyre sizes·305/30R22
305/30R22
Overall diameter 741.8 mm

305/30R22 — 741.8 mm tall, and what it swaps with

305/30R22 is 305 mm wide with a 30% sidewall on a 22-inch wheel. That sidewall is 91.5 mm, so the tyre stands 741.8 mm tall and turns 429.1 times per kilometre.

Section width
305 mm
Aspect ratio
30 %
Wheel size
22 in (558.8 mm)
Sidewall height
91.5 mm
Overall diameter
741.8 mm (29.2 in)
Circumference
2330.4 mm
Turns per km
429.1

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 305/30R22?

741.8 mm — the 558.8 mm wheel plus the 91.5 mm sidewall at top and bottom.

Q. How many turns per kilometre does 305/30R22 make?

Its circumference is 2330.4 mm, so 429.1 turns.

Q. What can I swap it for?

12 sizes stay within 3% of its diameter — the closest is 235/55R19 at 741.1 mm.

Q. Why is the sidewall 91.5 mm?

Because it is 30% of the 305 mm width. The aspect ratio is a proportion of the width, not a length.