Turkey T.C. Kimlik No Validator

The T.C. Kimlik No (TCKN) is the 11-digit national identity number assigned to every Turkish citizen by the Nüfus ve Vatandaşlık İşleri (NVI). It is used across HR onboarding, e-Government (e-Devlet), and banking KYC. Every TCKN carries two self-check digits, so a simple mistype can be caught instantly. This validator runs the official algorithm in your browser.

How it works

Treat the 11 digits as positions 1 through 11 (left to right). The first 9 digits are the body; digits 10 and 11 are check digits computed as follows:

1. Strip non-digits. The number must be 11 digits and the first digit must not be 0.
2. Let odd = sum of digits at positions 1, 3, 5, 7, 9.
3. Let even = sum of digits at positions 2, 4, 6, 8.
4. Digit 10 = ((odd × 7) − even) mod 10. If the intermediate value is negative, add 10 to bring it into the 0–9 range.
5. Digit 11 = (sum of the first 10 digits) mod 10.
6. The TCKN is valid when both computed check digits equal the actual 10th and 11th digits.

Example

Validate 10000000146. Digits are 1 0 0 0 0 0 0 0 1 4 6.

odd  = d1+d3+d5+d7+d9 = 1+0+0+0+1 = 2
even = d2+d4+d6+d8     = 0+0+0+0   = 0
d10  = ((2 × 7) − 0) mod 10 = 14 mod 10 = 4   ✓ (matches)
d11  = (1+0+0+0+0+0+0+0+1+4) mod 10 = 6 mod 10 = 6   ✓ (matches)

Both check digits match, so the TCKN is valid.

Notes

A valid checksum confirms the number is well-formed, not that the identity exists or is registered. Use official NVI / e-Devlet services for real verification. Everything here runs locally — the number never leaves your browser.