Coding rules of ID number: Citizen ID number is a characteristic combination code, which consists of 17-bit ontology code and a number or character (X) check code. From left to right are six-digit address code, eight-digit birthday date code, three-digit serial code and one-digit check code.

Among the 6-digit address codes, the first 2 digits represent provinces, municipalities directly under the Central Government and autonomous regions:

1 1- 15 ? Beijing, Tianjin, Hebei, Shanxi and Mongolia

2 1-23 ? Liao, Ji and hei

3 1-37 ? Shanghai, Jiangsu, Zhejiang, Anhui, Fujian, Jiangxi and Shandong

4 1-46 ? Henan, Hubei, Hunan, Guangdong, Guangxi and Qiong

50-54 ? Chongqing, Sichuan, Guizhou, Yunnan, Tibet

6 1-65 ? Shaanxi, Gansu, Qinghai, Ningxia and New China.

The last four said that cities and counties regretted hunger and prospered the country, and districts and counties.

The 8-digit birth date code adopts 8-digit fixed-length date representation: 4-digit year, 2-digit month and 2-digit day. The 3-digit sequence code indicates the order and sex of limbs born on the same day, with odd numbers representing males and even numbers representing females. Finally, the 1 parity code is represented by "0-9" and "x".

The check code is obtained by mathematical calculation. Check code calculation formula: (12-∑ (ai× wi) (mod11)) mod11. I- indicates the position serial number of the ID number from left to right, and the value is1-17; AI- the number representing the i-th position; Wi- the weighting factor for the i-th position. Calculation formula of weighting factor: wi = 2 (I-1) (mod11) The calculation result of check code is "0-10"1,where "/kloc-0" is used.