205/65R15 vs 225/55R16
225/55R16 is a safe swap for 205/65R15 by the usual ±3% rule: the diameter differs by +0.99%.
Speedometer and odometer
With 225/55R16 on a car calibrated for 205/65R15, the speedometer reads 59.4 mph when you're really doing 60, and the odometer under-counts by 1.0%.
| Speedo shows | Actual speed |
|---|---|
| 30 mph | 30.3 mph |
| 45 mph | 45.4 mph |
| 60 mph | 60.6 mph |
| 70 mph | 70.7 mph |
| 80 mph | 80.8 mph |
Other sizes close to 205/65R15
Questions
Can I replace 205/65R15 with 225/55R16?
225/55R16 is a safe swap for 205/65R15 by the usual ±3% rule: the diameter differs by +0.99%.
What's the difference between 205/65R15 and 225/55R16?
225/55R16 is 0.25" taller and 20 mm wider; the sidewall is -0.37". At an indicated 60 mph you'd actually be doing 60.6 mph.
Will 225/55R16 fit on 205/65R15 wheels?
No — 205/65R15 needs a 15" wheel and 225/55R16 a 16" wheel. This is a plus/minus-size swap that changes wheels too.