Compare two sizes
/R
/R
km/h
Enter the sizes as width / aspect R rim (e.g. 205/55 R16) for both tyres.
◎Diameter difference
+0.38%
Current diameter631.9 mm
New diameter634.3 mm
True speed100.4 km/h
The ideal diameter difference is under ±3%, otherwise the speedometer and ABS may be affected.
205/55R16 → 225/45R17: Diameter difference +0.38%