Comparison of tire sizes 285/70 R17 and 265/70 R18
285/70R17
285
Tire width 
70
Profile height 
R17
Tire diameter 
383
RPM per km 285mm200mm831mm2610mm
285
70
17
265
70
18
| Parameters Sizes | Old | New | |||
|---|---|---|---|---|---|
| Diameter, mm | 831 | 828 | -3 (-0.4%) | ||
| Width, mm | 285 | 265 | -20 (-7%) | ||
| Circumference, mm | 2610 | 2602 | -8 (-0.3%) | ||
| Profile height, mm | 200 | 186 | -14 (-7%) | ||
| RPM per km | 383 | 384 | +1 (+0.3%) | ||
| Clearance change, mm | -2 | ||||
| Result: | The diameter differs by -0.4%. | ||||
| Speedometer reading (km/h) | |
|---|---|
| Real speed (km/h) | 99.7 |
| Difference (km/h) | -0.3 |
Sizes for comparison of tires 285/70 R17
R17
R16 -1
R18 +1
Sizes for comparison of tires 265/70 R18
R18
R17 -1
R16 -2
R20 +2