Validator of Estonia Registrikood
Estonian business registry code (Äriregister / RIK) with two-tier Modulo 11.
About Estonian Registrikood
The Registrikood is the official company registration code issued by the Centre of Registers and Information Systems (RIK) in Estonia.
Every private limited company (OÜ), public company (AS), and non-profit organization registered in the Estonian Business Register possesses a unique 8-digit code.
Anatomy & Structure of Estonian Registrikood
The Registrikood consists of exactly 8 numeric digits:
| Position | Field | Length | Meaning & Rule | Example |
|---|---|---|---|---|
| 1 | Entity Type | 1 digit | 1 (Commercial entity OÜ/AS), 7 (State), 8 (NGO MTÜ), 9 (Foundation SA) | 1 |
| 2 to 7 | Base Number | 6 digits | Sequential registration number assigned by RIK | 000001 |
| 8 | Check Digit | 1 digit | Two-tier Modulo 11 integrity checksum | 8 |
Official Äriregister Algorithm (Two-Tier Modulo 11)
Verification of the first 7 digits using weighted arithmetic:
Sum = Σ (d[i] * w[i]); Remainder = Sum mod 11
- 1. Multiply the first 7 digits by weights [1, 2, 3, 4, 5, 6, 7].
- 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].
- 4. If second remainder is less than 10, use it; if still 10, check digit is 0.
- 5. Verify match with the 8th digit.