255/35R21 vs 265/30R22
265/30R22 is a safe swap for 255/35R21 by the usual ±3% rule: the diameter differs by +0.83%.
Speedometer and odometer
With 265/30R22 on a car calibrated for 255/35R21, the speedometer reads 59.5 mph when you're really doing 60, and the odometer under-counts by 0.8%.
| Speedo shows | Actual speed |
|---|---|
| 30 mph | 30.2 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 255/35R21
- 255/35R21 vs 255/40R20+0.01%
- 255/35R21 vs 285/35R20-0.62%
- 255/35R21 vs 265/40R21+4.71%
- 255/35R21 vs 275/35R21+1.97%
- 255/35R21 vs 295/35R21+3.93%
- 255/35R21 vs 255/40R21+3.58%
- 255/35R21 vs 265/35R21+0.98%
- 255/35R21 vs 295/35R20+0.37%
- 255/35R21 vs 245/35R21-0.98%
- 255/35R21 vs 325/30R21+2.32%
- 255/35R21 vs 315/30R21+1.47%
- 255/35R21 vs 285/35R21+2.95%
Questions
Can I replace 255/35R21 with 265/30R22?
265/30R22 is a safe swap for 255/35R21 by the usual ±3% rule: the diameter differs by +0.83%.
What's the difference between 255/35R21 and 265/30R22?
265/30R22 is 0.23" taller and 10 mm wider; the sidewall is -0.38". At an indicated 60 mph you'd actually be doing 60.5 mph.
Will 265/30R22 fit on 255/35R21 wheels?
No — 255/35R21 needs a 21" wheel and 265/30R22 a 22" wheel. This is a plus/minus-size swap that changes wheels too.