The Romanian CIF/CUI (Cod de Identificare Fiscala / Cod Unic de Inregistrare) is the tax identification number assigned to every company registered in Romania. Before you trust a tax code on an ANAF invoice, a procurement document or a supplier record, you can confirm it is internally well-formed with the official control-digit algorithm. This free validator runs that exact check in your browser.
How it works
The control digit of a CIF is computed with a fixed reversed weight string and a modulo-11 rule:
- Remove any
ROprefix and spaces, leaving 2 to 10 digits. - The last digit is the control digit. The remaining digits form the body.
- Right-align the body against the 9-position weight string
7, 5, 3, 2, 1, 7, 5, 3, 2— when the body has fewer than 9 digits, the unused weights on the left are simply ignored. - Multiply each body digit by its aligned weight and sum the products.
- Multiply the sum by 10, then take the remainder modulo 11.
- If the remainder is 10, the expected control digit is 0; otherwise it is the remainder itself.
- The CIF is valid when the expected control digit equals the actual last digit.
Example
Validate 14180297. The body is 1418029 (7 digits) and the control digit is 7.
Right-aligning the body against the weight string uses the last 7 weights 3, 2, 1, 7, 5, 3, 2 against digits 1, 4, 1, 8, 0, 2, 9 → 3 + 8 + 1 + 56 + 0 + 6 + 18 = 92. Then 92 × 10 = 920, and 920 mod 11 = 7. The expected control digit is 7, which matches, so the CIF is valid.
Notes
A valid checksum confirms the number is structurally correct, not that the entity is registered or VAT-active. Romanian VAT payers prefix the code with RO (for example RO14180297); the prefix is informational and does not change the check digit. Everything here runs locally — your tax code never leaves your device.