Chinese ID Number Analyzer – Decode & Validate 18-Digit IDs Online
Enter an 18-digit Chinese ID number to instantly extract address, birth date, gender, and verify the checksum – processed locally for security
Enter an 18-digit ID number to auto-decode information
Example: 11010119900307663X
This feature requires a client-side environment to run.
Usage Tips
- Enter an 18-digit Chinese national ID number (uppercase X allowed)
- The system instantly parses the address code, birth date, sequence code, and checksum
- The address code maps to province, city, and district based on the GB/T 2260 standard
- The 17th digit indicates gender: odd for male, even for female
- The checksum is automatically calculated and verified using the ISO 7064:1983.MOD11-2 algorithm
- All analysis is performed locally; your ID number never leaves your device
Chinese ID Number Analyzer: Decode the Hidden Information in Your ID
What is a Chinese ID Number Analyzer?
A Chinese ID Number Analyzer is a tool designed to parse the 18-digit national identification number issued to every Chinese citizen. This unique identifier is not a random sequence but a structured code that encapsulates personal data including registered domicile address, date of birth, gender, and a validation checksum. Our online ID number decoder processes these digits locally within your browser, ensuring no sensitive data is ever uploaded to a server. By entering a valid identity card number, users can instantly retrieve the embedded information without manual lookup tables or complex calculations. The tool serves as both an educational resource to understand the national ID standard GB 11643-1999 and a practical utility for verifying ID number integrity. Whether you need to confirm a person's province of origin, check the accuracy of a birthdate on file, or validate an ID number's authenticity using the modulo 11-2 algorithm, this free ID card decoder provides a secure and immediate solution.
How the Chinese ID Number is Structured and Verified
The Chinese national ID number, governed by the GB 11643-1999 standard, is an 18-digit composite code. The first six digits constitute the address code, representing the administrative division where the holder's household is registered, specifically down to the county or district level. Digits seven through fourteen represent the birth date in the format YYYYMMDD, which is why the ID number can be used as a reliable age calculator and birthday validator. The fifteenth to seventeenth digits are the sequence code, which distinguishes individuals born in the same region on the same day; crucially, the seventeenth digit acts as a gender indicator. The eighteenth digit is the checksum, computed using the ISO 7064:1983.MOD11-2 algorithm. This check digit verification process involves multiplying each of the first seventeen digits by a specific weighting factor, summing the products, dividing by eleven to obtain a remainder, and mapping that remainder to a final check digit through a predefined lookup table. If the calculated value matches the input digit, the ID number passes validation. This rigorous mathematical principle underpins the authenticity check performed by our tool, making it a robust ID number validator.
How to Use the ID Card Decoder and Verification Tool
Using this ID card verification tool is straightforward and requires no technical expertise. Begin by typing a complete 18-digit Chinese ID number into the input field at the top of the page. You can manually type the number, paste it from your clipboard, or use the provided example button to see the tool in action. The analyzer reacts instantly to your input, performing live parsing without needing a submit button. The results panel will display the parsed address code with the corresponding province, city, and district names; the extracted birth date with year, month, and day; the sequence code with a clear gender assignment; and the checksum comparison. A green "Valid" badge indicates the ID number's checksum matches the calculated value, while a red "Invalid" badge signals a discrepancy. For user convenience, the tool also maintains a history of recent searches, each displayed in a masked format to protect privacy. All computations happen locally via JavaScript, meaning your ID number never transmits over the internet, offering a privacy-first approach to identity data decoding.
Frequently Asked Questions About the ID Number Analyzer
What information can be extracted from a Chinese ID number?
From a valid 18-digit Chinese national identification number, you can reliably extract the holder's registered permanent residence at the county or district level, their exact date of birth, their gender, and verify the number's formal validity through its checksum. The first six digits, known as the address code, correspond to a specific administrative division per the national GB/T 2260 standard, which our tool resolves to display province, city, and district names. Digits seven through fourteen directly encode the birth year, month, and day. The seventeenth digit reveals gender: an odd number denotes male, and an even number denotes female. Finally, the eighteenth digit serves as a check code, mathematically derived from the preceding seventeen digits, which allows the tool to function as a checksum validator. It is important to note that the ID number does not contain information such as the person's name, current address, ethnicity, or photo.
Is it safe to use an online ID number decoder?
Security and privacy are paramount when handling personal identification numbers. Our Chinese ID number analyzer has been explicitly designed with a privacy-first architecture. All parsing, address lookup logic, and checksum calculations are executed entirely within your web browser using client-side JavaScript. At no point is the ID number you enter transmitted to any remote server, logged, or stored externally. The tool operates without server-side processing, meaning your data never leaves your device. This local computation model ensures that you can safely verify and decode ID numbers without the risk of data interception or unauthorized collection, making it a genuinely secure environment for performing identity document validation and information retrieval.
Why does the validator show "Invalid" for my ID number?
An "Invalid" status from the checksum verification can occur for several reasons. The most straightforward is a typographical error during entry; a single mistyped digit can cause the final check digit to mismatch the calculated value. Our tool also validates the birth date segment, so an invalid date like February 30th or a month greater than 12 will trigger an error. Another common scenario is using a fabricated or example number that does not conform to the ISO 7064:1983.MOD11-2 algorithm. Very old ID numbers (15-digit format issued before the upgrade to 18 digits) are not directly supported unless they have been correctly converted. Additionally, some valid ID numbers from extremely new administrative divisions might have address codes not fully recognized by the lookup module, though the checksum itself should remain mathematically correct. Ensure your input consists of exactly 18 characters, with the last character being a digit or uppercase "X".
Can this tool determine if an ID number is real or just mathematically valid?
This tool performs a mathematical validation based on the official algorithm, confirming that the checksum is consistent with the preceding seventeen digits and that the internal date and address codes meet format requirements. A "Valid" result means the number is structurally sound according to the GB 11643-1999 standard. However, this does not constitute a legal verification that the ID number is currently active, belongs to a real person, or matches any government database. A criminal could fabricate a mathematically correct checksum for a non-existent person. True verification of an ID number's real-world status requires authorized querying of the Public Security Bureau's national population information database, which is not publicly accessible. Our tool should be used for data validation, educational understanding, and preliminary checking, not as a definitive proof of identity.
How does the 17th digit gender indicator work?
The gender indicator in a Chinese ID number is remarkably simple and reliable. The 17th digit, which is the third and final digit of the sequence code, directly maps to the holder's biological sex. If this digit is an odd number (1, 3, 5, 7, 9), the holder is recorded as male. If it is an even number (0, 2, 4, 6, 8), the holder is recorded as female. This deterministic relationship is part of the national standard and has no exceptions. The sequence code itself serves to order individuals sharing the same birth date and registered address, and the gender association was intentionally designed into the system to provide an immediate, machine-readable sex identifier without requiring additional data fields. This feature makes the ID number a highly efficient code for demographic statistics and administrative processing.
What are the limitations of the address code lookup in this tool?
The address code lookup resolves the first six digits to a province, city, and district based on the GB/T 2260 standard for administrative divisions of China. While comprehensive for current and most historical codes, certain limitations exist. Newly established districts or merged administrative zones may have codes that are not yet reflected in the local dataset. Very old ID numbers might reference divisions that have since been reorganized, and the lookup will provide the last-known mapping. Additionally, the tool shows the registered domicile at the time of ID issuance, which may not represent the holder's current residence. The parsed address information identifies the county or district level but does not extend to specific streets or communities. For general identity verification and demographic analysis, the resolution provided is sufficient and accurate for the vast majority of valid address codes.