Check a Thai 13-digit tax ID for typos
A Thai taxpayer number has 13 digits. The last one is calculated from the first 12, so one mistyped or misread digit usually shows up. Paste one or many numbers below to check them right away.
Check tax IDs
Checked in your browser. Nothing is sent. A correct check digit means the number is well-formed, not that it is right: a wrong 3rd digit is never caught. It also does not show that the business exists or is VAT-registered.
What this check tells you, and what it doesn't
- Whether the number has 13 digits and its last digit matches the first 12.
- It never catches a wrong 3rd digit: the formula gives that position a weight divisible by 11. Passing the check is not proof; compare with the original document.
- It does not show that the business exists, is still trading or is VAT-registered. Check that with the Revenue Department.
Keep tax IDs intact in Excel
- Format the column as text before pasting, or convert files with a tool that keeps identifiers as text.
- If Excel displays 1.05536E+12, inspect all digits in the formula bar. If digits were lost or rounded, compare with the original file.
- ORDODAY's Excel invoice register stores tax IDs as text.
Is my file uploaded?
No. This tool runs inside your browser on this device. ORDODAY's servers never receive the file, and the page's security policy blocks it from sending file data anywhere.
PrivacyLimits worth knowing
- Checks the number's form only; it does not look up the business.
- Up to 500 lines at a time.