Comparison of tire sizes 185/55 R15 and 175/55 R15

185/55R15
185 Tire width
55 Profile height
R15 Tire diameter
545 RPM per km
185mm102mm585mm1836mm
185
55
15
175
55
15
Parameters Sizes Old New
Diameter, mm585574-11 (-1.9%)
Width, mm185175-10 (-5.4%)
Circumference, mm18361802-34 (-1.9%)
Profile height, mm10296-6 (-5.9%)
RPM per km545555+10 (+1.8%)
Clearance change, mm-6
Result:
The diameter differs by -1.9%.
Speedometer reading (km/h)
Real speed (km/h)98.1
Difference (km/h)-1.9

Sizes for comparison of tires 185/55 R15

R15
R14 -1
R16 +1
R13 -2
R17 +2

Sizes for comparison of tires 175/55 R15

R15
R14 -1
R16 +1
R13 -2
R17 +2