Brazil CNPJ validator (mod-11)
The CNPJ (Cadastro Nacional da Pessoa Jurídica) is Brazil’s company taxpayer number: 12 base digits followed by 2 mod-11 check digits computed with the standard CNPJ weight cycle. This validator recomputes both check digits, rejects reserved all-identical sequences, and shows the formatted number.
Type a CNPJ to verify it instantly — everything runs in your browser, with nothing uploaded.