Turkish ID Number (T.C. Kimlik No) Validator
Check the two check digits of an 11-digit Turkish identity number, or work them out from the first nine digits.
Enter all 11 digits to check them, or the first 9 to get the last two. Spaces are ignored.
Enter a number to see the result.
The result says only whether the number has the right form and check digits. It does not tell you whether the number has been issued or who it belongs to.
Test numbers
Test values only. Do not use them as the number of a real person.
Random 11-digit numbers with correct check digits, for development and testing. A random number can match one that has really been issued.
How the check digits are calculated
- NVİ (the General Directorate of Population and Citizenship Affairs) states that the number has 11 digits and that the last two are calculated from the first nine. It shares the algorithm with public institutions but does not publish it.
- The tool uses the formula in general public use. 10th digit: add the 1st, 3rd, 5th, 7th and 9th digits and multiply by 7, subtract the sum of the 2nd, 4th, 6th and 8th digits, and keep the last digit of the result (modulo 10).
- 11th digit: the last digit of the sum of the first ten digits.
- The first digit is never 0.
- According to NVİ the number says nothing about the person: not their sex, age, religion or place of birth, and a relative's number cannot be worked out from it.
- Everything runs in your browser. The numbers you enter are not sent to LeedyBox or saved.
Source: Nüfus ve Vatandaşlık İşleri Genel Müdürlüğü: T.C. Kimlik No İşlemleri · Last checked:
Wrong result? If a number that was really issued is marked as wrong, email us. Please do not send the number itself: tell us which check digit failed, or send a generated test number that shows the problem.
Does a sentence on this page sound unnatural in your language? Let us know that too.
How to use
- Type the 11 digits of the number. The tool checks the 10th and 11th digits as you type.
- If you have only the first nine digits, enter those: the tool shows the two check digits and the full number.
- For software tests, choose how many numbers you need and press Generate. They have correct check digits but are random.
Frequently asked questions
How are the last two digits of a T.C. Kimlik No calculated?
In the formula in general use, the 10th digit is (7 × the sum of the 1st, 3rd, 5th, 7th and 9th digits − the sum of the 2nd, 4th, 6th and 8th digits) modulo 10, and the 11th digit is the sum of the first ten digits modulo 10. For 123456789: 7 × 25 − 20 = 155, so the 10th digit is 5; 45 + 5 = 50, so the 11th is 0, giving 12345678950.
Is this the official algorithm?
NVİ confirms that the last two digits are calculated from the first nine and says it shares the algorithm with public institutions, but it does not publish the formula. The tool uses the formula that is in general public use and says so on the page.
Does a valid result mean the number belongs to someone?
No. Many 11-digit numbers have correct check digits without ever having been issued. Only NVİ's own systems can confirm that a number belongs to a person.
Do the digits say anything about the person?
No. NVİ states that the number contains no meaningful information such as sex, age, religion or place of birth, and that a relative's number cannot be derived from it.
Can a T.C. Kimlik Numarası start with 0?
No. The first digit is never 0, so an 11-digit number starting with 0 is not valid even if its check digits work out.