In fact, in many countries there is an exam called "International Baccalaureat" which students can pass after twelve years of school education.
In India, one sits in for "Secondary School Certificate Examination" after ten years of school education or "Senior Secondary School Certificate Examination" after twelve years of school education.
In fact, one can have a pick of the translation of a certificate on the basis of number of years one studies in order to obtain that certificate. This is not the best or foolproof method but can be useful in case one is thinking of getting an equivalence in educational system of a different country/ culture.
I hope that this helps!!!