235/45R18
235/45R18 ships as an OEM size on the Honda Accord, Hyundai Kona. At 26.33″ diameter with a 4.16″ sidewall (45% of section width), this size turns 766 revolutions per mile.
About 235/45R18
Factory fitments for 235/45R18 include the Honda Accord, Hyundai Kona — meaning replacement tires in this size see steady demand and broad brand availability. At 26.33″ overall diameter, 235/45R18 turns 766 revolutions per mile, which is the reference point the factory speedometer and odometer were calibrated against. The 45% aspect ratio gives it a low-profile sidewall that delivers sharp steering response but transmits road imperfections. 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 225/45R18 drops diameter by 1.35%, which stays within the ±3% fitment safe zone for most vehicles. Stepping up to 215/50R18 adds 0.52% 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 26.33″ 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 aliases235/45R18
- Diameter
- 26.33″ / 668.7mm
- Section Width
- 9.25″
- Sidewall
- 4.16″ / 105.75mm
- Circumference
- 82.71″
- Revs/Mile
- 766
215/45R18
- Diameter
- 25.62″ / 650.7mm
- Section Width
- 8.46″
- Sidewall
- 3.81″ / 96.75mm
- Circumference
- 80.48″
- Revs/Mile
- 787
Speedometer & Diameter Impact
At an indicated 60 mph, your actual speed is 58.38 mph (93.96 km/h). Your speedometer reads 2.69% high versus actual speed.