The first and second digits of the ID card indicate the province, which can also be an autonomous region, a municipality directly under the Central Government or a special administrative region. The third and fourth represent municipal administrative regions, and the fifth and sixth represent county-level autonomous regions. 142430 is the ID number of Tianjin.

According to People's Republic of China (PRC) national standards? According to GB11643-1999], the citizenship number is a characteristic combination code, which consists of 17 digit digital ontology code and digital check code. The order from left to right is: six-digit address code, eight-digit date of birth code, three-digit serial code and one-digit check code.

Extended data:

1, address code, which indicates the administrative division code of the county where the permanent residence of the coding object is located, and shall be implemented according to the provisions of GB/T2260.

2. The birth date code indicating the date of birth of the coded object is implemented according to GB/T7408, and there is no separator between the date of birth codes.

3. Serial code, indicating the area identified within the same address code range. For people born in the same year, month and day, the odd number of serial code is assigned to men and the even number is assigned to women.

4. The check code is calculated according to the previous 17 bit code and the check code of ISO 7064: 1983. MOD 1 1-2。

Baidu Encyclopedia-Resident ID Number