Comparison of tire sizes 265/65 R18 and 255/70 R18
265/65R18
265
Tire width 
65
Profile height 
R18
Tire diameter 
397
RPM per km 265mm172mm802mm2519mm
265
65
18
255
70
18
| Parameters Sizes | Old | New | |||
|---|---|---|---|---|---|
| Diameter, mm | 802 | 814 | +12 (+1.5%) | ||
| Width, mm | 265 | 255 | -10 (-3.8%) | ||
| Circumference, mm | 2519 | 2558 | +39 (+1.5%) | ||
| Profile height, mm | 172 | 179 | +7 (+4.1%) | ||
| RPM per km | 397 | 391 | -6 (-1.5%) | ||
| Clearance change, mm | +6 | ||||
| Result: | The diameter differs by 1.5%. | ||||
| Speedometer reading (km/h) | |
|---|---|
| Real speed (km/h) | 101.5 |
| Difference (km/h) | 1.5 |
Sizes for comparison of tires 265/65 R18
R18
R17 -1
R19 +1
R16 -2
R20 +2
Sizes for comparison of tires 255/70 R18
R18
R17 -1
R19 +1
R16 -2
R20 +2