Comparison of tire sizes 285/45 R19 and 305/45 R18
285/45R19
285
Tire width 
45
Profile height 
R19
Tire diameter 
431
RPM per km 285mm128mm739mm2322mm
285
45
19
305
45
18
| Parameters Sizes | Old | New | |||
|---|---|---|---|---|---|
| Diameter, mm | 739 | 732 | -7 (-0.9%) | ||
| Width, mm | 285 | 305 | +20 (+7%) | ||
| Circumference, mm | 2322 | 2299 | -23 (-1%) | ||
| Profile height, mm | 128 | 137 | +9 (+7%) | ||
| RPM per km | 431 | 435 | +4 (+0.9%) | ||
| Clearance change, mm | -4 | ||||
| Result: | The diameter differs by -0.9%. | ||||
| Speedometer reading (km/h) | |
|---|---|
| Real speed (km/h) | 99 |
| Difference (km/h) | -1 |
Sizes for comparison of tires 285/45 R19
R19
R18 -1
R20 +1
R17 -2
R21 +2
Sizes for comparison of tires 305/45 R18
R18
R17 -1
R19 +1
R16 -2
R20 +2
