Rigorous structural check-digit auditing by country
Verify exact check-digit formulas using our RFC Validator (Mexico), inspect control digits via our RUC Validator (Peru), audit citizen keys in the CURP Validator, or verify European structures with our DNI/NIE Validator and IBAN Validator.
Local checks for sensitive identifiers
These validators apply format and check-digit formulas in your browser memory without querying external databases. A result confirms mathematical structure, not identity, ownership, current status, or authenticity before an authority.