Vergi Kimlik Numarası Checker (Türkiye)
Check that a Vergi Kimlik Numarası is correctly formed and that its check digit computes, before you put it on an invoice. Nothing is sent anywhere.
- Free
- No sign-up
- Nothing uploaded
- Updated for 2026
- Last reviewed October 2026
- Reviewed by the Owoode team
- ₺ TRY
- KDV 20%
- Tax number (VKN or TCKN)
- A4
- English
Enter a number above.
Example: 4540536920
How the number is built and checked
A tax number has two forms in Turkey: ten digits for legal entities and for foreigners without a Turkish or foreign identity number, and eleven digits where it is a Turkish citizen's T.C. Kimlik Numarası or a foreign resident's Yabancı Kimlik Numarası (VUK article 8; Tax Identification Number Circular Series 4). A checker should therefore accept both lengths.
The revenue administration (GİB) does not offer an open name-lookup. A taxpayer's own number is shown after login to the Dijital Vergi Dairesi or the e-Devlet service "Vergi Kimlik Numarası Sorgulama" on turkiye.gov.tr. To test a counterparty, the e-Belge site (ebelge.gib.gov.tr) publishes the registered-user lists for e-Fatura and e-İrsaliye and the list of taxpayers registered for e-Arşiv; presence on a list decides which type of invoice applies. No official check-digit algorithm is published.
What this does and does not tell you
This page checks arithmetic, not registration. Every Vergi Kimlik Numarası carries a check digit calculated from the digits before it, which is what catches a typo. Confirming that a business is genuinely registered means asking Revenue Administration (GİB), because only they hold the register.