Validate numeric and alphanumeric CNPJs in bulk and see which check digit failed.
Numeric or alphanumeric, with or without dots, slash and dash. Lowercase letters are accepted. Up to 1000 per check.
Paste a CNPJ to check it as you type.
Validation runs entirely in your browser. Nothing is sent or stored. A valid result means the number is well formed, not that the company exists or is active.
This CNPJ validator checks Brazilian company registration numbers against the official check digit algorithm as you type, in both formats: the classic 14 digit CNPJ and the alphanumeric CNPJ the Receita Federal issues from July 2026, with letters in the first 12 positions. Paste one number or a whole list, one per line, with or without punctuation, in upper or lower case. Valid entries come back formatted (00.000.000/0000-00), labelled numeric or alphanumeric, with the branch read from positions 9 to 12 (0001 is the headquarters). Invalid ones get a precise reason: wrong length, a letter where a digit belongs, a repeated sequence, or which check digit is wrong and what it should be. Handy for migrating validators to the new format, cleaning supplier lists and debugging rejected forms. Nothing leaves your browser.