CPF Validator
Check if a CPF is mathematically valid by verifying its check digits.
Valid CPF
Formatted:
Digits only:
Invalid CPF
The check digits don't match. Please verify the number.
API Endpoint
GET /api/tools/validate/cpf/{cpf}
Response includes: isValid, formatted, unformatted
How CPF Validation Works
The CPF (Cadastro de Pessoa Fisica) is the Brazilian tax identification number for individuals. It consists of 11 digits, where the last two are verification digits calculated using a specific algorithm.
CPF Structure
- First 9 digits: Base number (includes regional code)
- Last 2 digits: Check digits (calculated from the first 9)
Regional Codes
The 9th digit of a CPF indicates the issuing region:
- 0 - RS
- 1 - DF, GO, MS, MT, TO
- 2 - AC, AM, AP, PA, RO, RR
- 3 - CE, MA, PI
- 4 - AL, PB, PE, RN
- 5 - BA, SE
- 6 - MG
- 7 - ES, RJ
- 8 - SP
- 9 - PR, SC
Check Digit Algorithm
The check digits are calculated using weighted multiplication and modular arithmetic (mod 11). Our validator performs this calculation and compares the result with the provided digits.
Privacy Note
CPF numbers are personal data protected by Brazilian privacy laws (LGPD). This tool only validates the mathematical structure - it does not verify identity or store any data.