Tyre Size Calculator, Rim Width Calculator and New Tyre Size Generator all in one (try to keep the radius within + or - 1%).

It's important to keep to the cars original tyre circumference, what we do is fit larger alloy wheels and a smaller profile tyre to compensate, otherwise gearing, speedo, engine management could be affected, this tool can be used to ensure this. Can also be used to find cheaper alternative sized tyres, therefore saving you money.