Taiwan ID Number Validator
Check a Taiwan national ID or resident certificate number, see its region and gender code, or generate test numbers.
Check a number
Enter a 10-character number.
Generate a test number
Generated numbers pass the checksum and are for testing forms and software only. They may coincide with a real person's number by chance. Never use them to impersonate anyone.
How the check digit works
The first letter is converted to a two-digit code (A = 10, B = 11 … but I = 34, O = 35, W = 32, Z = 33, following the official table). Those two digits and the nine digits that follow are each multiplied by a weight (1, 9, 8, 7, 6, 5, 4, 3, 2, 1, 1), summed, and the number is valid only when the total is divisible by 10. The last digit is chosen so that this works out, which is why a single typo almost always fails the check.
The three formats
- National ID: a letter for the household registration region, then 1 (male) or 2 (female), then 8 digits ending with the check digit.
- New resident certificate, issued since January 2021: same shape, but the second character is 8 (male) or 9 (female), so it fits every system built for national IDs.
- Old resident certificate: two letters, where the second letter encodes gender (A or C male, B or D female) and its code's last digit takes part in the checksum.
Privacy
Numbers you type are checked on your device and never sent anywhere. Nothing is logged.