2021 BMW 230i — Coupe
The 2021 BMW 230i Coupe shipped with 3 different factory tire sizes, depending on the wheel package it left the factory with (this can also reflect a staggered front/rear setup). Check your tire sidewall or door placard to confirm which one applies to your vehicle.
This trim shipped with more than one tire size (staggered fitment, front/rear, or optional wheel package). Confirm which one matches your vehicle by checking your tire sidewall or door placard.
205/50R17
| Section width | 205 mm |
|---|---|
| Aspect ratio (sidewall height) | 50% (102.5 mm) |
| Rim diameter | 17" |
| Overall tire diameter | ~25.1" |
| Revolutions per mile | ~804 |
- Check 205/50R17 price at TireRack
- Check 205/50R17 price at SimpleTire
- Check 205/50R17 price at Priority Tire
Some links on this page are affiliate links — see our disclosure.
225/40R18
| Section width | 225 mm |
|---|---|
| Aspect ratio (sidewall height) | 40% (90 mm) |
| Rim diameter | 18" |
| Overall tire diameter | ~25.1" |
| Revolutions per mile | ~804 |
- Check 225/40R18 price at TireRack
- Check 225/40R18 price at SimpleTire
- Check 225/40R18 price at Priority Tire
Some links on this page are affiliate links — see our disclosure.
225/40R18 (front)245/35R18 (rear)
- Check 225/40R18 (front)245/35R18 (rear) price at TireRack
- Check 225/40R18 (front)245/35R18 (rear) price at SimpleTire
- Check 225/40R18 (front)245/35R18 (rear) price at Priority Tire
Some links on this page are affiliate links — see our disclosure.
Other 2021 BMW 230i trims
- Convertible 205/50R17 / 225/40R18 / 225/40R18 (front)245/35R18 (rear)
- Convertible M Sport 225/40R18 / 225/40R18 (front)245/35R18 (rear)
- Coupe M Sport 225/40R18 / 225/40R18 (front)245/35R18 (rear)
- Track Package 225/40R18 front / 245/35R18 rear
- xDrive Convertible 205/50R17 / 225/40R18 / 225/40R18 (front)245/35R18 (rear)
- xDrive Convertible M Sport 225/40R18 / 225/40R18 (front)245/35R18 (rear)
- xDrive Coupe 205/50R17 / 225/40R18 / 225/40R18 (front)245/35R18 (rear)
- xDrive Coupe M Sport 225/40R18 / 225/40R18 (front)245/35R18 (rear)
How to read a tire size
A tire size like 225/45R17 breaks down into three parts:
the first number is the section width in millimeters
(the tire's width from sidewall to sidewall), the second is the
aspect ratio — the sidewall's height as a percentage of
that width — and the number after the "R" is the rim
diameter in inches. A letter prefix (P or LT) indicates
Passenger or Light Truck construction; its absence usually means
Euro-metric sizing.
Some trucks and off-road tires instead use "flotation" sizing, like
37X12.50R17 — here the numbers are the tire's overall
diameter and width in inches directly, with the rim diameter last.
Always verify against the tire information placard on your driver's-side door jamb or your owner's manual before purchasing — tire size can vary by factory option package even within the same trim.