Comparison of tire sizes 275/55 R17 and 285/55 R18
275/55R17
275
Tire width 
55
Profile height 
R17
Tire diameter 
433
RPM per km 275mm151mm734mm2307mm
275
55
17
285
55
18
| Parameters Sizes | Old | New | |||
|---|---|---|---|---|---|
| Diameter, mm | 734 | 771 | +37 (+5%) | ||
| Width, mm | 275 | 285 | +10 (+3.6%) | ||
| Circumference, mm | 2307 | 2421 | +114 (+4.9%) | ||
| Profile height, mm | 151 | 157 | +6 (+4%) | ||
| RPM per km | 433 | 413 | -20 (-4.6%) | ||
| Clearance change, mm | +19 | ||||
| Result: | The diameter differs by 5%. | ||||
| Speedometer reading (km/h) | |
|---|---|
| Real speed (km/h) | 104.9 |
| Difference (km/h) | 4.9 |
Sizes for comparison of tires 275/55 R17
R17
R16 -1
R18 +1
R15 -2
R19 +2
Sizes for comparison of tires 285/55 R18
R18
R17 -1
R19 +1
R16 -2
R20 +2