225/50R15 vs 175/65R15
175/65R15 is a safe swap for 225/50R15 by the usual ±3% rule: the diameter differs by +0.41%.
Speedometer and odometer
With 175/65R15 on a car calibrated for 225/50R15, the speedometer reads 59.8 mph when you're really doing 60, and the odometer under-counts by 0.4%.
| Speedo shows | Actual speed |
|---|---|
| 30 mph | 30.1 mph |
| 45 mph | 45.2 mph |
| 60 mph | 60.2 mph |
| 70 mph | 70.3 mph |
| 80 mph | 80.3 mph |
Other sizes close to 225/50R15
- 225/50R15 vs 195/65R15+4.70%
- 225/50R15 vs 185/65R15+2.56%
- 225/50R15 vs 185/60R15-0.50%
- 225/50R15 vs 195/60R15+1.49%
- 225/50R15 vs 205/50R16+0.89%
- 225/50R15 vs 205/50R15-3.30%
- 225/50R15 vs 195/50R16-0.76%
- 225/50R15 vs 195/55R15-1.73%
- 225/50R15 vs 205/60R15+3.47%
- 225/50R15 vs 185/55R15-3.55%
- 225/50R15 vs 185/55R16+0.64%
- 225/50R15 vs 175/70R14-0.89%
Questions
Can I replace 225/50R15 with 175/65R15?
175/65R15 is a safe swap for 225/50R15 by the usual ±3% rule: the diameter differs by +0.41%.
What's the difference between 225/50R15 and 175/65R15?
175/65R15 is 0.10" taller and 50 mm narrower; the sidewall is +0.05". At an indicated 60 mph you'd actually be doing 60.2 mph.
Will 175/65R15 fit on 225/50R15 wheels?
Both use a 15" rim, so the wheel diameter matches; check the wheel's width range for a 175 mm tire and the fender clearance.