230/40 R18 Tires
Everything we know about the 230/40 R18 tire size: 4 owner reviews covering 16,040 miles of driving, and EU label data for the tires you can actually buy in it.
- 4owner reviews
- 16,040 milescovered on them
What does 230/40 R18 mean?
A 230/40 R18 tire is 230 mm wide, its sidewall is 40% of that width (92 mm) tall, and it fits a 18 inch wheel. That gives an overall diameter of roughly 641 mm.
| Section width | 230 mm |
|---|---|
| Sidewall height | 92 mm |
| Rim diameter | 18" (457 mm) |
| Overall diameter | ≈ 641 mm |
| Circumference | ≈ 2,014 mm |
| Revolutions per km | ≈ 496 |
| Revolutions per mile | ≈ 799 |
Also written as
230/40R18 230/40 ZR18 230-40-18 230 40 18
Figures are calculated from the nominal size. A loaded, rolling tire runs a few percent smaller, and true widths vary slightly between makes.
What cars use 230/40 R18 tires?
The cars most often running this size in our owner reviews. Each links to the best rated tires for that exact car.
What drivers say about their 230/40 R18 tires
The most recent owner reviews fitted in this size, in their own words.
Drive on 230/40 R18 tires?
Review your tires and help the next driver choose. It takes about five minutes, and every review on this page came from a driver who took them.
Where this data comes from
Owner ratings are submitted through the review form on this site, naming the tire, the size and the distance covered, and are checked by hand before publication. Test results come from independent published tire tests indexed by size, and label values from the EU EPREL database.
About the TR Score
The Tire Reviews Score rates each tire out of 10 using independent test results and the full body of owner reviews, so you can check a car-specific ranking against the wider evidence.
Who does the testing
Every test published as a Tire Reviews test is run by Jonathan Benson, who has been testing tires independently since 2007.

