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CPF (Individual Taxpayer Registry) Validator

Check if a CPF is valid. Validation is performed using the official check digit algorithm.

ℹ️ How it Works

The CPF is validated using an algorithm that checks the two check digits:

  • The first digit is calculated by multiplying the first 9 digits by weights from 10 to 2
  • The second digit is calculated by multiplying the first 10 digits by weights from 11 to 2
  • CPFs with all identical digits are considered invalid
  • To verify the validity of a CPF with the Federal Revenue, access the official website: CPF Consultation - Federal Revenue

Facts about the CPF Validator

  • The CPF Validator checks the integrity of the 11-digit number.
  • The validation uses the official Modulo 11 algorithm.
  • The tool identifies CPFs with invalid check digits.
  • The tool does not verify the status of the CPF with the Federal Revenue.

Frequently Asked Questions

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