CNP Validator
Enter a 13-digit Romanian CNP to check its structure and control digit. If it is valid, the tool reads back the date of birth, sex, and county of registration that the number encodes.
How It Works
A CNP is not a random string. It follows the pattern S YY MM DD JJ NNN C, where every part has a meaning. The first digit, S, gives the sex and the century of birth. The next six digits are the date of birth as year, month, and day. Two digits, JJ, are the county where the number was registered. Three digits, NNN, are a sequential number, and the final digit, C, is a control digit that ties the whole number together.
The control digit is what makes a CNP self-checking. Each of the first twelve digits is multiplied by a fixed weight from the sequence 2, 7, 9, 1, 4, 6, 3, 5, 8, 2, 7, 9. The twelve products are added up, and the total is divided by 11. The remainder is the control digit, except that a remainder of 10 becomes 1. If the digit at the end does not match this result, the number is not a valid CNP.
Worked Example
Take the sample CNP 1630615123457, which is an example and does not belong to anyone. The first digit 1 means a man born between 1900 and 1999. The next six digits, 630615, give 15 June 1963. The county code 12 is Cluj. To check the last digit, multiply 1, 6, 3, 0, 6, 1, 5, 1, 2, 3, 4, 5 by the weights above and add the results, which comes to 216. Dividing 216 by 11 leaves a remainder of 7, and the final digit is 7, so the control digit matches and the number is valid.
When You Would Use This
This helps whenever a CNP has to be entered correctly on a form. A payroll or HR clerk keying in a new employee's details, a notary preparing a contract, or someone filling in an online application can paste the number here first and catch a mistyped digit before it causes a rejected form or a mismatch later. It is also a quick way to understand what a CNP on a document is telling you, since it spells out the birth date, sex, and county in plain terms.
Frequently Asked Questions
What is a CNP?
The CNP, or Cod Numeric Personal, is the 13-digit personal identification number issued to every Romanian citizen and to registered foreign residents. It appears on the national ID card, the passport, and most official paperwork.
What does the validator confirm?
It confirms that the 13 digits form a structurally correct CNP: the encoded date is a real calendar date, the county code exists, and the final control digit matches the other twelve. It cannot tell you whether a real person holds that number.
How is the sex and birth date read from the number?
The first digit encodes both sex and the century of birth. For example 1 is a man born between 1900 and 1999, 2 is a woman in the same period, and 5 and 6 cover men and women born from 2000 onward. The next six digits are the year, month, and day.
What do the two digits after the birth date mean?
They are the county code, showing where the CNP was registered. Codes 01 to 40 cover the counties and Bucharest, 41 to 46 are the six sectors of Bucharest, and 51 and 52 are Calarasi and Giurgiu.
Can I use this to generate a CNP?
No, and that is deliberate. This is a validator, not a generator. It checks a number you already have; it will not fabricate one for you.
Is my CNP stored or sent anywhere?
No. The check runs entirely in your browser. Nothing you type is uploaded or saved, so you can check a real CNP without it leaving your device.