Comparison of tire sizes 245/60 R18 and 255/60 R17
245/60R18
245
Tire width 
60
Profile height 
R18
Tire diameter 
424
RPM per km 245mm147mm751mm2360mm
245
60
18
255
60
17
| Parameters Sizes | Old | New | |||
|---|---|---|---|---|---|
| Diameter, mm | 751 | 738 | -13 (-1.7%) | ||
| Width, mm | 245 | 255 | +10 (+4.1%) | ||
| Circumference, mm | 2360 | 2318 | -42 (-1.8%) | ||
| Profile height, mm | 147 | 153 | +6 (+4.1%) | ||
| RPM per km | 424 | 431 | +7 (+1.7%) | ||
| Clearance change, mm | -7 | ||||
| Result: | The diameter differs by -1.7%. | ||||
| Speedometer reading (km/h) | |
|---|---|
| Real speed (km/h) | 98.2 |
| Difference (km/h) | -1.8 |
Sizes for comparison of tires 245/60 R18
R18
R17 -1
R19 +1
R16 -2
R20 +2
Sizes for comparison of tires 255/60 R17
R17
R16 -1
R18 +1
R15 -2
R19 +2
