The 255/45R20 is a common tire size for SUVs and crossovers such as Toyota RAV4, Honda CR-V, and Ford Explorer.
With a 114.8 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.
Compared to the baseline 265/50R20, this tire's overall diameter differs by -4.6% — a speedometer calibrated for 265/50R20 would read 104.8 km/h at an actual 100 km/h.
When replacing, verify that your wheel well can accommodate the 737.5 mm overall diameter. Keep speedometer deviation within ±3% for safety and legal compliance.
| Tire Code | 255/45R20 |
| Section Width | 255 mm |
| Aspect Ratio | 45% |
| Rim Diameter | 20" |
| Sidewall Height | 114.8 mm |
| Overall Diameter | 737.5 mm / 29.04" |
| Circumference | 2316.9 mm / 91.22" |
| Revolutions per km | 431.6 |
| Revolutions per mile | 694.6 |
| Tire Code | OD (mm) | Δ mm | Δ % | Speedo at 100 km/h |
|---|---|---|---|---|
| 255/45R18 | 686.7 | -50.8 | -6.9% | 107.4 |
| 255/45R19 | 712.1 | -25.4 | -3.4% | 103.6 |
| 245/45R20 | 728.5 | -9.0 | -1.2% | 101.2 |
| 255/45R20 (current) | 737.5 | — | — | 100.0 |
| 265/45R20 | 746.5 | +9.0 | +1.2% | 98.8 |
| 255/50R20 | 763.0 | +25.5 | +3.5% | 96.7 |