>>>>We have an application which negotiates with license plates. It is focused to be international. It currently supports Canada, United States and another country. I would like to know how many characters you are usually reserving for such a field in your application knowing that it could be used to store license plates from all over the world.
>>>
>>>In my country longest is 11 characters. Unicode not needed. We don't use turkish special letters for plates. Just use numbers and american letters excluded X,W,Q.
>>
>>The only one of 11 characters I can see here http://en.wikipedia.org/wiki/Vehicle_registration_plates_of_Turkey is a 'vanity' plate.
>
>I thought 99 XXX 9999 is possible. But it seem Vikipedia correct and me is wrong. Our biggest city is Istanbul and this table is formal: http://gib.gov.tr/fileadmin/user_upload/Plaka_Harf/Istanbul.htm
>
>I forgot vanity plates. I'm not sure if there is limitation about vanity plates, I saw much more longer vanity plates. I never thougt vanity plates at my applications and never got any feedback about it...
>

Vanity plates (at least in USA) have to conform to the max allowed number of characters for any plate. For example, in Massachusetts (where I live) the plate cannot be more than 6 characters and I need 7 for my vanity plate. I have been waiting forever for the state to increase the number :(