Chinese ID Card Validation Algorithm
A valid Chinese ID card number consists of 17 digits representing region, date, and sequence numbers, plus 1 check digit. The check digit calculation follows these rules:
First, calculate the weighted sum of the first 17 digits using weights: {7, 9, 10, 5, 8, 4, 2, 1, 6, 3, 7, 9, 10, 5, 8, 4, 2}. Then compute Z = sum % 11. Finally, map Z to the ...
Posted on Tue, 12 May 2026 14:23:56 +0000 by heinrich