205/50R16 vs 245/45R16
245/45R16 is a safe swap for 205/50R16 by the usual ±3% rule: the diameter differs by +2.54%.
Speedometer and odometer
With 245/45R16 on a car calibrated for 205/50R16, the speedometer reads 58.5 mph when you're really doing 60, and the odometer under-counts by 2.5%.
| Speedo shows | Actual speed |
|---|---|
| 30 mph | 30.8 mph |
| 45 mph | 46.1 mph |
| 60 mph | 61.5 mph |
| 70 mph | 71.8 mph |
| 80 mph | 82.0 mph |
Other sizes close to 205/50R16
Questions
Can I replace 205/50R16 with 245/45R16?
245/45R16 is a safe swap for 205/50R16 by the usual ±3% rule: the diameter differs by +2.54%.
What's the difference between 205/50R16 and 245/45R16?
245/45R16 is 0.61" taller and 40 mm wider; the sidewall is +0.31". At an indicated 60 mph you'd actually be doing 61.5 mph.
Will 245/45R16 fit on 205/50R16 wheels?
Both use a 16" rim, so the wheel diameter matches; check the wheel's width range for a 245 mm tire and the fender clearance.