The passport number itself is not normalised, can have different lengths and structures depending both on the country and when it was issued, can use the same number for different passports issued by different countries, and usually does not include any information about the issuing country.
However, the MRZ (machine readable zone, the two lines at the bottom of the bio page) is standardised and includes both the issuer country and the passport number (and more information).
Credit:stackoverflow.com‘
5 Mar, 2024
4 Mar, 2024