Brazilian CPF Validator
Enter a CPF, formatted or not, and see whether its check digits are valid.
This tool validates Brazilian documents only.
How it works
Validate Brazilian CPF numbers by checking their verification digits according to the official algorithm. Everything runs locally in your browser. The CPF (Brazil's individual taxpayer registry number) has 11 digits: the first 9 identify the person, and the last 2 are check digits computed from the previous ones using a modulo-11 algorithm. This validator automatically strips dots and dashes, recomputes both check digits from the first 9 numbers, and compares them against the ones provided — with no server lookup. Important: a CPF being mathematically valid doesn't mean it was actually issued to someone; this tool only validates the format and check digits.