China ID Card Validator
Validate 18-digit Chinese resident ID numbers (居民身份证). Verify checksum, decode birth date, gender, and province. All processing is done locally in your browser.
📋 Batch Validate (one ID per line)
How Chinese ID Cards Work
The Chinese Resident Identity Card (居民身份证) uses an 18-character identifier structured as follows:
- Digits 1–6: Region code (省、市、县/区)
- Digits 7–14: Date of birth (YYYYMMDD)
- Digits 15–17: Sequential code (odd = male, even = female)
- Digit 18: Check digit (0–9 or X), computed using ISO 7064 Mod 11-2
🔒 Privacy Notice
All validation runs 100% in your browser. No ID numbers are ever transmitted to any server, stored, or logged.
The 18th character is computed from the first 17 using the ISO 7064 Mod 11-2 algorithm. A valid checksum means the number is mathematically consistent, but does not mean it belongs to a real person.
When the calculated check digit equals 10, it is represented as "X" (the Roman numeral for 10) to keep the ID at 18 characters.