The 235/45R18 is a common tire size for midsize sedans such as Toyota Camry, Honda Accord, and Hyundai Sonata.
With a 105.8 mm sidewall (45% aspect ratio), this tire offers a balanced blend of ride comfort and handling precision — versatile for both city driving and spirited cornering.
This is one of the most popular tire sizes for 18" rims, frequently used as a reference point when comparing speedometer accuracy across similar sizes.
OE on the Honda Accord Sport (2013-2017 9th-gen) and Toyota Camry SE (XV70 2018+ 235/45R18 94V). Load index 94W or 98Y reinforced. Sidewall is more forgiving than 235/40R18 — a common OE choice for mid-size sedans positioned as "sporty but daily-able".
Mainstream sedan sizes balance compound longevity against light all-season handling. When replacing, match the OE speed rating (H or V on most trims) — installing a lower rating voids many manufacturer load-test certifications and is illegal on autobahn-rated vehicles. Wheel-well clearance is rarely a concern at this rim diameter; speedometer drift across factory alternatives stays well inside the ±3% legal window.
| Tire Code | 235/45R18 |
| Section Width | 235 mm |
| Aspect Ratio | 45% |
| Rim Diameter | 18" |
| Sidewall Height | 105.8 mm |
| Overall Diameter | 668.7 mm / 26.33" |
| Circumference | 2100.8 mm / 82.71" |
| Revolutions per km | 476.0 |
| Revolutions per mile | 766.1 |
| Tire Code | OD (mm) | Δ mm | Δ % | Speedo at 100 km/h |
|---|---|---|---|---|
| 235/45R17 | 643.3 | -25.4 | -3.8% | 103.9 |
| 235/40R18 | 645.2 | -23.5 | -3.5% | 103.6 |
| 225/45R18 | 659.7 | -9.0 | -1.3% | 101.4 |
| 235/45R18 (current) | 668.7 | — | — | 100.0 |
| 245/45R18 | 677.7 | +9.0 | +1.3% | 98.7 |
| 235/45R19 | 694.1 | +25.4 | +3.8% | 96.3 |
| 235/55R18 | 715.7 | +47.0 | +7.0% | 93.4 |