Tyre Calculator

It's important to keep the cars original tyre circumference, we fit larger alloy wheels and a smaller profile tyre to compensate, otherwise gearing, speedo and engine management can be affected.


Tyre Size to Compare
Diameter Circumference Fits Wheel Rim
Show / Hide specific tyre size to compare against.
When speedometer reads mph/kph your actual speed will be   mph/kph.
Possible new tyre sizes, which will maintain the original tyre circumference or rolling radius
within + or - 1% which is adjustable below, mph/kph is also adjustable below;
Tyre Size   Diameter        Circumference    Difference  Speedo  Fits Wheel Rim
----------  --------------  ---------------  ----------  ------  --------------
195/70 R14  628mm / 24.72"  1973mm / 77.68"  -0.95 %     69.33   5.5x14 to 7x14
185/75 R14  634mm / 24.96"  1992mm / 78.43"   0.00 %     70.00   5x14 to 6.5x14
175/80 R14  636mm / 25.04"  1998mm / 78.66"   0.30 %     70.21   5x14 to 6.5x14
205/60 R15  628mm / 24.72"  1973mm / 77.68"  -0.95 %     69.33   5.5x15 to 7x15
215/60 R15  640mm / 25.20"  2011mm / 79.17"   0.95 %     70.67   6x15 to 7.5x15
195/65 R15  634mm / 24.96"  1992mm / 78.43"   0.00 %     70.00   5.5x15 to 7x15
225/50 R16  632mm / 24.88"  1985mm / 78.15"  -0.35 %     69.75   6x16 to 7.5x16
205/55 R16  632mm / 24.88"  1985mm / 78.15"  -0.35 %     69.75   5.5x16 to 7x16
195/60 R16  640mm / 25.20"  2011mm / 79.17"   0.95 %     70.67   5.5x16 to 7x16
245/40 R17  628mm / 24.72"  1973mm / 77.68"  -0.95 %     69.33   8x17 to 9.5x17
255/40 R17  636mm / 25.04"  1998mm / 78.66"   0.30 %     70.21   8.5x17 to 10x17
225/45 R17  634mm / 24.96"  1992mm / 78.43"   0.00 %     70.00   7.5x17 to 9x17
205/50 R17  636mm / 25.04"  1998mm / 78.66"   0.30 %     70.21   5.5x17 to 7x17
285/30 R18  628mm / 24.72"  1973mm / 77.68"  -0.95 %     69.33   9.5x18 to 11x18
295/30 R18  634mm / 24.96"  1992mm / 78.43"   0.00 %     70.00   10x18 to 11.5x18
245/35 R18  628mm / 24.72"  1973mm / 77.68"  -0.95 %     69.33   8x18 to 9.5x18
255/35 R18  636mm / 25.04"  1998mm / 78.66"   0.30 %     70.21   8.5x18 to 10x18
215/40 R18  630mm / 24.80"  1979mm / 77.91"  -0.65 %     69.54   7x18 to 8.5x18
225/40 R18  638mm / 25.12"  2004mm / 78.90"   0.60 %     70.42   7.5x18 to 9x18
315/25 R19  640mm / 25.20"  2011mm / 79.17"   0.95 %     70.67   10.5x19 to 12x19
255/30 R19  636mm / 25.04"  1998mm / 78.66"   0.30 %     70.21   8.5x19 to 10x19
215/35 R19  634mm / 24.96"  1992mm / 78.43"   0.00 %     70.00   7x19 to 8.5x19
225/35 R19  640mm / 25.20"  2011mm / 79.17"   0.95 %     70.67   7.5x19 to 9x19
Width ( to ) Profile ( to ) to
Difference MPH/KPH TyreCalc version 2.3 rel 15/04/2015. ©2018.