English interface

Thai tax ID format checker

Check the structure and check digit of a 13-digit Thai tax ID.

ReviewedModerate-impact
Saves this tool's name on this device only (up to 20). No form values.
Only visible result text is included. Form fields are not read. Review sensitive values before sharing.
Enter 13 digits

Local format/check-digit check only. It does not confirm registration or identity with a government database.

How to use it

  1. Read the scope and effective-date note before entering information.
  2. Enter the requested values and review any validation message.
  3. Check the result, assumptions and cited source before relying on it.

Important limitation

A valid check digit does not confirm registration or identity with the Revenue Department.

The interactive form is fully localized in English.

Reviewed 2026-08-26; next review 2027-02-26.

Core calculations, cited sources and main test cases have been reviewed within the stated scope.

Traceable review record

Review history

Site changelog

This is the recorded review history available in the repository, not an inferred release history. Dates are added only when evidence is recorded.

  1. Current review snapshot recorded

    Core calculations, cited sources and main test cases have been reviewed within the stated scope.

    Method version: review-2026-08-26