Reading 235/45R18 94W
235 is the section width in millimetres. 45 is the aspect ratio — the sidewall height as a percentage of that width. R means radial construction. 18 is the wheel diameter in inches.
The numbers after the size matter just as much: the load index (94 in this example) is the tire's load capability, and the letter is the speed rating. On a heavy, quick EV, matching or exceeding both is not optional.
Where to look on your car
Easiest: crouch beside a front tire and read the raised lettering on the sidewall. Alternative: open the driver's door and read the placard on the door jamb, which lists the original size and recommended pressures.
If the wheels or tires were changed by a previous owner, the sidewall is what is actually fitted — the placard is what the car left the factory with. We compare both.
Model 3, Model Y, Model S, Model X, Cybertruck
Each model has been offered with several wheel diameters over its production run, and larger wheels mean shorter sidewalls and fewer tire choices. Some configurations use different front and rear sizes, which changes both purchasing and rotation.
Rather than publish fitment tables that may not match your specific car, we verify against your vehicle. That is the only way to be right about load index and speed rating as well as size.
Not sure?
Send us your Tesla model, year and tire size — or just a photo of the tire sidewall — and we will help identify the correct options for your car.
Want a specialist to look at it?
Ron's Tire & Wheel has been fitting tires in Southern California since 1972, with two shops in North Hollywood and one in Pasadena. Send your Tesla details through Find My Tesla Tires, or call the shop nearest you.