Validator of Lithuania Asmens Kodas
Lithuanian personal code (Gyventojų registras) with two-tier Modulo 11.
About Lithuanian Asmens Kodas
The Asmens Kodas (AK) is the universal personal identity code assigned to Lithuanian citizens and foreign residents by the State Enterprise Centre of Registers (Registrų centras).
It is the primary unique identifier used across healthcare, tax administration, public registry services, and banking institutions in Lithuania.
Anatomy & Structure of Lithuanian Asmens Kodas
The Asmens Kodas consists of 11 numeric digits formatted as GYYMMDDSSSC:
| Position | Field | Length | Meaning & Rule | Example |
|---|---|---|---|---|
| 1 | Gender & Century | 1 digit | 1/2 (male/female 19th c.), 3/4 (20th c.), 5/6 (21st c.) | 3 |
| 2 to 7 | Birth Date | 6 digits | Gregorian calendar birthdate (YYMMDD) | 800101 |
| 8 to 10 | Daily Sequence | 3 digits | Sequential birth registration index | 123 |
| 11 | Check Digit | 1 digit | Official two-tier Modulo 11 checksum | 5 |
Official Gyventojų registras Algorithm (Two-Tier Modulo 11)
Two rounds of weighted arithmetic checking:
Sum = Σ (d[i] * w[i]); Remainder = Sum mod 11
- 1. Multiply the first 10 digits by weights [1, 2, 3, 4, 5, 6, 7, 8, 9, 1].
- 2. If sum mod 11 is less than 10, the check digit is the remainder.
- 3. If remainder is 10, recalculate using secondary weights [3, 4, 5, 6, 7, 8, 9, 1, 2, 3].
- 4. If second remainder is less than 10, use it; if still 10, the check digit is 0.
- 5. Check digit must equal the 11th digit.