#### Circumference change

Here you can adjust the maximum allowed change in tyre circumference for alternative tyre sizes included in the search.

A change in tyre circumference has a similar percentage effect on the speedometer error since the speed of the car is calculated based on the rotation speed of the tyre. If the circumference of the tyre increases by one per cent, the speed of the car also increases by one per cent while the speedometer reading stays the same.

The maximum allowed change in tyre circumference without a compulsory modification inspection is 5%. When buying bigger tyres, please make sure that they will fit your car even under a heavy load.