245/35R19 vs 225/45R18
225/45R18 is a safe swap for 245/35R19 by the usual ±3% rule: the diameter differs by +0.86%.
Speedometer and odometer
With 225/45R18 on a car calibrated for 245/35R19, the speedometer reads 59.5 mph when you're really doing 60, and the odometer under-counts by 0.9%.
| Speedo shows | Actual speed |
|---|---|
| 30 mph | 30.3 mph |
| 45 mph | 45.4 mph |
| 60 mph | 60.5 mph |
| 70 mph | 70.6 mph |
| 80 mph | 80.7 mph |
Other sizes close to 245/35R19
- 245/35R19 vs 245/40R18-0.14%
- 245/35R19 vs 245/40R19+3.75%
- 245/35R19 vs 235/40R19+2.52%
- 245/35R19 vs 255/40R19+4.97%
- 245/35R19 vs 255/35R19+1.07%
- 245/35R19 vs 275/35R19+3.21%
- 245/35R19 vs 225/40R19+1.30%
- 245/35R19 vs 235/35R19-1.07%
- 245/35R19 vs 225/45R19+4.74%
- 245/35R19 vs 275/35R18-0.67%
- 245/35R19 vs 285/35R19+4.28%
- 245/35R19 vs 265/35R19+2.14%
Questions
Can I replace 245/35R19 with 225/45R18?
225/45R18 is a safe swap for 245/35R19 by the usual ±3% rule: the diameter differs by +0.86%.
What's the difference between 245/35R19 and 225/45R18?
225/45R18 is 0.22" taller and 20 mm narrower; the sidewall is +0.61". At an indicated 60 mph you'd actually be doing 60.5 mph.
Will 225/45R18 fit on 245/35R19 wheels?
No — 245/35R19 needs a 19" wheel and 225/45R18 a 18" wheel. This is a plus/minus-size swap that changes wheels too.