Comparison of tire sizes 235/65 R18 and 245/70 R17
235/65R18
235
Tire width 
65
Profile height 
R18
Tire diameter 
417
RPM per km 235mm153mm763mm2396mm
235
65
18
245
70
17
| Parameters Sizes | Old | New | |||
|---|---|---|---|---|---|
| Diameter, mm | 763 | 775 | +12 (+1.6%) | ||
| Width, mm | 235 | 245 | +10 (+4.3%) | ||
| Circumference, mm | 2396 | 2434 | +38 (+1.6%) | ||
| Profile height, mm | 153 | 172 | +19 (+12.4%) | ||
| RPM per km | 417 | 411 | -6 (-1.4%) | ||
| Clearance change, mm | +6 | ||||
| Result: | The diameter differs by 1.6%. | ||||
| Speedometer reading (km/h) | |
|---|---|
| Real speed (km/h) | 101.6 |
| Difference (km/h) | 1.6 |
Sizes for comparison of tires 235/65 R18
R18
R17 -1
R19 +1
R16 -2
R20 +2
Sizes for comparison of tires 245/70 R17
R17
R16 -1
R18 +1
R15 -2
R19 +2