Turkish T.C. Kimlik No Validator
Validate Turkish T.C. Kimlik Numarası identity numbers in real time.
Turkish T.C. Kimlik Validation
Validates the 11-digit format, leading non-zero rule, and dual checksum formulas.
Ensures compliance for Turkish KYC, onboarding, and public service integrations.
Anatomy & Structure of T.C. Kimlik Numarası
The Turkish Identification Number consists of 11 digits in 3 parts:
| Position | Field | Length | Meaning & Rule | Example |
|---|---|---|---|---|
| 1 | Leading Digit | 1 digit | Official constraint: cannot be zero (valid range: 1 to 9) | 1 |
| 2 to 9 | Base Individual Number | 8 digits | Sequential civil identifier assigned by NVİ | 23456789 |
| 10 & 11 | Interdependent Check Digits | 2 digits | Two cross-calculated checksum digits | 05 |
Official Algorithm (Two Interdependent Check Digits — Law No. 5490/2006)
Calculation of the 10th and 11th check digits for T.C. Kimlik:
d10 = ((oddSum * 7 - evenSum) mod 10); d11 = (sumFirst10 mod 10)
- 1. Compute oddSum = d1 + d3 + d5 + d7 + d9 (odd positions).
- 2. Compute evenSum = d2 + d4 + d6 + d8 (even positions).
- 3. 10th digit: d10 = (oddSum × 7 - evenSum) mod 10 (add 10 if negative).
- 4. 11th digit: d11 = (d1 + d2 + ... + d10) mod 10.
- 5. Number is valid if both check digits match and d1 is not 0.