The editor of Downcodes will give you an in-depth understanding of the mystery of China’s resident identity card number! The ID card number, this seemingly simple string of 18 digits, contains a wealth of personal information. It is not only a symbol of identity, but also a key tool for identity recognition and verification in modern society. This article will explain in detail the composition of the ID card number, including the specific meaning of the area code, date of birth code, sequence code and check code and their importance in practical applications, and answer some common questions to help you better understand This mysterious digital code.
The ID card number is a unique identification code for each Chinese citizen and consists of 18 digits. Each digit has its own specific meaning, which is divided into: area code, date of birth code, sequence code, and check code. Among them, the area code is the part of the ID number that most intuitively reflects the location of the citizen’s registered residence.
The area code refers to the first 6 digits of the ID card number. They represent the geographical location of the holder's household registration, from province, city to district and county, and each two digits represents a different level. For example, 110000 represents Beijing City, and 110101 represents Dongcheng District, Beijing City. China's area codes are set according to the "Administrative Division Code of the People's Republic of China", which allows everyone's household registration location to be quickly determined through their ID number.
The area code not only reflects the holder's registered residence, but also reflects China's complex administrative division structure. Through these six digits, the three-level administrative divisions of province, city, district and county where the holder of the certificate was born or main residence can be quickly identified. This has important practical significance for public security, social security, traffic management and other fields.
The date of birth code follows the area code and occupies the 7th to 14th digits of the ID number. This part uses eight digits to indicate the date, month and day of birth of the certificate holder, in the format of "YYYYMMDD". For example, 19900204 represents February 4, 1990. This design allows personal age information to be intuitively reflected in the ID number.
The introduction of date of birth codes facilitates rapid age verification in various legal, administrative and commercial activities. In areas such as education, employment, marriage registration, prohibition of minors purchasing tobacco and alcohol, etc., the actual age of the holder can be determined by directly reading the ID number, avoiding forgery or misunderstanding.
The sequence code is the 15th to 17th digits in the ID number. Its purpose is to distinguish people born in the same year, the same month, the same day, and the same area. Among them, odd numbers are assigned to men and even numbers are assigned to women. That is, the gender of the holder can be determined by the last digit of the sequence code.
The design of the sequential code not only reflects gender distinction, but also increases the uniqueness and complexity of the ID number. As the population grows, the number of citizens in the same area and with the same date of birth increases. More combinations can be generated through the three-digit sequence code to ensure that each person's ID number is unique.
The check code is the last digit of the ID number. It is calculated based on the first 17 digits in accordance with the ISO 7064:1983, MOD 11-2 standard and is used to verify the correctness of the ID number. The calculation of the check code is more complicated and is calculated through specific formulas and weighting factors. If the calculation result is 10, the check digit is represented by the Roman numeral X.
The function of the verification code is to prevent the mistaken entry or forgery of the ID number. The validity of the ID number can be quickly verified through the verification algorithm. Even if the first 17 digits are randomly fabricated without a correctly calculated check code, such an ID number will be recognized as invalid by the system.
Each digit of the ID card number is carefully designed, not only containing basic information such as the holder's region, date of birth, gender, etc., but also ensuring the authenticity and uniqueness of the number through a check code. This system greatly facilitates work in many aspects such as population management, social services, and law enforcement, and is an indispensable identity identification and verification tool in modern society.
1. What does each digit of the ID number mean? The ID number is composed of 18 digits, each digit represents a different meaning, as follows:
The first 6 digits: represent the administrative division code of the area where the ID card holder is located. In China, the province, city or region where a person is located can be determined based on these 6 digits. Digits 7-14: represent the date of birth of the ID card holder. The first two digits represent the year of birth, the middle two digits represent the month, and the last two digits represent the number of days. For example, 031221 indicates that the holder was born on December 21, 2003. Digits 15-17: represent the gender of the ID card holder. Odd numbers represent men, even numbers represent women. The 18th digit: is the verification code calculated based on the first 17 digits, used to verify the validity of the ID card.2. How to know the holder’s information through the ID card number? The following information can be learned through the ID number:
Administrative division code of the region: The first 6 digits can be used to determine the province, city or region where a person is located. Date of birth: The date of birth of the ID card holder can be known from the 7th to 14th digits. Gender: The 15th to 17th digits can identify whether the holder is male or female. However, due to privacy reasons, an individual's specific name and other details are not available through the ID number.3. What other information does the ID number contain? In addition to the individual's region, date of birth and gender, the ID number also carries some special meanings:
Province information: The first 2 digits represent the province where the holder is located. For example, 11 represents Beijing City and 44 represents Guangdong Province. City information: The first 4 digits represent the city where the holder is located. For example, 1101 represents the municipal district of Beijing, and 4401 represents Guangzhou City, Guangdong Province. Date of birth: The holder's date of birth can be known through 7-14 digits, and the age of the holder can also be calculated based on this. Gender: The gender of the holder can be determined by the 15th to 17th digits. Odd numbers represent males and even numbers represent females. Through this information, the basic background and characteristics of the ID card holder can be understood to a certain extent.I hope that the interpretation by the editor of Downcodes can help you better understand the composition and meaning of the Chinese Resident ID Number. This article is for reference only, please refer to official regulations for specific information.