How to use
Run a clean first pass
- Enter a 10-digit ID number, or load a sample number.
- Click validate to see the pass/fail badge and decoded summary.
- Read the checksum ladder to understand how each step affects the final result.
Input
Enter a 10-character ID (1 letter + 9 digits).
Enter an ID number, then validate.
Result
Format and checksum verification.
Waiting to validate
--
Enter a Taiwan national ID number.
VALIDIssuing region
--
Checksum ladder
| Pos | Digit | Wt | Prod | Sum |
|---|
Total: --
|
Remainder: --
How it works
This tool validates Taiwan national ID numbers locally in your browser. No data is sent to any server. The first letter maps to an issuing region, and the remaining 9 digits are verified through a weighted checksum.
Common uses: testing form validation rules during development, understanding the weighted checksum algorithm, and teaching the step-by-step calculation process.
Note: This tool only verifies format correctness. It cannot confirm whether an ID actually exists. Results are for reference only.
Quick guide
Use cases, answers, and nearby tools
Compact below-tool notes that help first-run users and repeated visitors move faster without changing the main interface.
Chinese search: 身分證 驗證、身分證 檢查碼、身分證號碼 格式、台灣 ID 驗證
Examples
Real jobs this page helps with
- Format and checksum validationEnter an ID number to confirm whether the region code, gender prefix, and checksum are all correct.
- Educational referenceUse the checksum ladder to explain Taiwan ID validation logic to colleagues or students.
FAQ
What people usually want to know
- Does this upload my ID number?
- No. All validation runs locally in your browser. No data is sent to any server.
- Does passing validation mean the ID exists?
- No. Passing only means the format and checksum are correct, not that the number exists in government records.