What do you think of the ID number?

The composition of the ID number indicates that:

1, the top six places correspond to provinces and cities, and they are sorted according to the address of the first ID card, and will not change according to the change of address or household registration; 7 to 14 is the date of birth.

2. Bits15 to 17 are serial codes for people born in the same year and the same month in the area marked by the same address code. Among them, 17 represents gender, odd numbers are men and even numbers are women; The last bit is the check code.

3. Arrangement rules: the ID number consists of 18 digits, respectively: the first 1 and the two digits indicate the code of the province; The first 3 or 4 digits indicate: the code of the city; The first 5 or 6 digits indicate the area code.

4. The number 7~ 14 indicates the date of birth, 7, 8, 9 and 10 are the years, 1 1 2 are the months, 13 and 14. Numbers 15 and 16 indicate the codes of local police stations; The number 17 indicates gender: odd numbers indicate men and even numbers indicate women; The number 18 is the check code: the check code can be a number from 0 to 9, sometimes represented by X.

5. The tail number X is the check code as the tail number, which is calculated by the numbering unit according to a unified formula. If someone's suffix is 0~9, X will not appear, but if the suffix is 10, X will have to be used instead.

6, because if you use 10 as the ending number, this person's ID card will become 19 digits, and the number of 19 digits violates the national standard, and the computer application system in China does not recognize the ID card number of 19 digits. X is the Roman numeral 10. Replacing 10 with X can ensure that the citizen ID card meets the national standards.