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Tax ID & national ID validator
Check a Turkish tax number (VKN) or national ID (TCKN) for typos before issuing an e-invoice.
Your data never leaves your browser and is never stored.
| Number | Type | Status |
|---|
How to use it
- Enter the number: 10 digits is a VKN, 11 digits a TCKN.
- For a bulk check, put one number per line.
- Invalid ones are shown with the reason.
How it works
The last digit of a VKN or TCKN is a check digit computed from the others. The tool applies that algorithm and catches typos. It can’t tell whether the number is registered or who it belongs to.
Frequently asked questions
Does a valid number exist?
It follows the algorithm. Whether it is registered needs an official lookup.
Which one for a sole trader?
Usually the TCKN for sole traders and the VKN for companies. Ask the other party to be sure.
Are the numbers stored?
No. Everything runs in your browser.
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