> a national ID number isnt usually publicly available info
replyA couple of counterexamples:
Italy's "fiscal code" is generated with a simple algorithm which can be executed manually:
https://en.wikipedia.org/wiki/Italian_fiscal_code
Sweden's "personal identity number" is public information and can be looked up by anyone:
https://en.wikipedia.org/wiki/Personal_identity_number_(Swed...
Belgian National Number is your birth date, then an increment from 1 to 999 for every baby born that day, then a base-97 checksum.
replyNot sure if still the case: odd numbers for males and even numbers for females.
replyThis also means a person’s Belgian RRN can change.
Yep, but they do not change on sex change, IIRC.
replyI wrote a system for a medical lab decades ago and IIRC I did actually have to change some RRN's manually. It's been a while so I'm not 100% sure, but I do think the changes were due to switching gender.
replyThis is the leaked draft: https://statewatch.org/wp-content/uploads/2026/05/wk_5183_20...
replyIt's not clear how it is supposed to work in detail. But it sounds like it could be implemented in a way that makes illegitimate queries possible. It doesn't sound like they want to really ensure that you can catch those.
In multiple European countries, national ID numbers are public information that can be searched by name and address (i.e. Sweden)
replyI played with Estonia’s e-residency and they use asymmetric cryptography for everything so the ID is public but does nothing without the corresponding private key.
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