The article explains the logic and structure of the Estonian Personal Identification Number, and how each user can turn on the validation when entering a new person.

Code Structure

1. Gender and century of birth

The 1st digit of the personal identification code contains information about the owner's gender (odd number - male, even number - female) as well as the first two digits of the year of birth.  

The first number is  

• "1" if 1800 ... 1899. a born man  

• "2" if 1800 ... 1899. a born woman  

• "3" if 1900 ... 1999. a born man  

• "4" if 1900 ... 1999. a born woman  

• "5" if 2000 ... 2099. a born man  

• "6" if 2000 ... 2099. a born woman  

• "7" if 2100 ... 2199. a born man  

• "8" if 2100 ... 2199. a born woman  

2-7. Date of birth

The ID second to sevens character indicates their year, month, and day of birth, in the format YYMMDD.

For example, if the date of birth is the 2nd of May 1976, then the Personal ID character 2-7 will be 760503.

8-10. Individual number

Individual numbers consist of 3 digits issued by the government. This is a serial number to distinguish those born on the same day in digits (000 to 999). For those born before 2013, hospital identification may be included.  

11. Control character

The verification number of the personal identification code shall be formed by the method "Module 11", using stage I or II weights:  

Grade I Weight: 1 2 3 4 5 6 7 8 9 1  

Grade II weight: 3 4 5 6 7 8 9 1 2 3  

This means that the first ten digits of the personal identification code are each multiplied by the first-degree weight, and the products are added together. The resulting amount is divided by 11. If the quotient is not equal to 10, the remainder is a control number.  

If the remainder equals 10, then the first 10 digits of the code are each multiplied by the Grade II weight. The products are added together. The resulting amount is divided by 11. If the residue is less than 10, the residue obtained is a control number. If the residue is equal to 10, the check digit is 0.  

Example 1.

Personal code 37605030299 verification:  
Sum = 1 × 3 + 2 × 7 + 3 × 6 + 4 × 0 + 5 × 5 + 6 × 0 + 7 × 3 + 8 × 0 + 9 × 2 + 1 × 9 = 108.  
The remainder of 108 divided by 11 is 9. (108/11 ~ 9.8. So the integer is 9. Here 9 * 11 = 99. Subtracting 108 - 99 = 9, which is the remainder).  

So the last number of the personal code 37605030299 must be 9.  

Example 2.

A person with identification code 34501234215 was born on January 23, 1945 (... 450123 ...). He is a man (3 ...), whose personal identification code was registered in the Pärnu CMB Department (... 42 ...) and was the first male person on that day (... 1.). The verification code for the personal identification number is 5 (... 5).  

Example 3.

If a girl was born on March 13, 1994 in Põlva County, her ID is most likely 49403136515, or if she was the second girl born in the area on that day, 49403136526. 

Validation

Open

If the entered ID does not match the validation criteria, the user will receive the message as below, the system would still allow saving the ID with the user’s consent.

Open