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CPR number contains Age and Sex. It's date of birt DD MM YY. Plus four digits where you can read the sex from. I think it's even vs uneven numbers.

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It's honestly worse. DDMMYYY (the last Y is from a lookup table to know if it's 18YY, 19YY or 20YY). If a person is born before October 2007 you can even do a checksum using the last digits to verify that the number is "correct" (not necessarily in use). And yes, last digit is an even number for women, and uneven for men.

.. decimal place for interestingly gendered?

I think you get to pick even or uneven yourself if you're don't identify as male or female and you can have a new CPR if you change gender.

There is some interesting details that may require you to change your name, if you want the last digit changed. That means if you're name is Kurt, you can't have a CPR number ending in an even number, because Kurt is only an approved name for men. If your name is Kim, Storm, Charlie, Orla, Lykke or some other unisex name it's not a problem.

OK clear, thank you.

This is most worrying for the Danish. Come to think of it, it's worrying for all o f us.

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