235/60R18
235/60R18 ships as an OEM size on the Audi Q5, Buick Envision, Honda CR-V. At 29.10″ diameter with a 5.55″ sidewall (60% of section width), this size turns 693 revolutions per mile.
About 235/60R18
Factory fitments for 235/60R18 include the Audi Q5, Buick Envision, Honda CR-V — meaning replacement tires in this size see steady demand and broad brand availability. At 29.10″ overall diameter, 235/60R18 turns 693 revolutions per mile, which is the reference point the factory speedometer and odometer were calibrated against. The 60% aspect ratio gives it a balanced sidewall — enough compliance for daily comfort without vague steering. The 18″ rim pairing is typical for full-size truck, premium SUV, and sport-sedan platforms, so compatible wheels are easy to source new or used. Going one step shorter to 225/60R18 drops diameter by 1.62%, which stays within the ±3% fitment safe zone for most vehicles. Stepping up to 225/65R18 adds 1.42% diameter — also inside the safe window, with marginally taller ride height. If you are shopping for a direct replacement, any tire within roughly ±0.7″ of the 29.10″ stock diameter (about ±2% in percentage terms) will keep ABS, TPMS, and odometer readings inside the vehicle's designed tolerance.
Compare with another size
275/65R18 or "33" for inch aliases235/60R18
- Diameter
- 29.1″ / 739.2mm
- Section Width
- 9.25″
- Sidewall
- 5.55″ / 141mm
- Circumference
- 91.43″
- Revs/Mile
- 693
215/60R18
- Diameter
- 28.16″ / 715.2mm
- Section Width
- 8.46″
- Sidewall
- 5.08″ / 129mm
- Circumference
- 88.46″
- Revs/Mile
- 716
Speedometer & Diameter Impact
At an indicated 60 mph, your actual speed is 58.05 mph (93.43 km/h). Your speedometer reads 3.25% high versus actual speed.