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Tax and payments · Free · no signup

Brazilian CPF validator

Check whether a Brazilian CPF is valid by computing its module-11 check digit. The tool also shows the tax region of the number. Free, no sign-up, no data sent.

Brazilian CPF validator

Check whether a CPF actually exists: the last two digits are derived from the first nine by modulo 11. The ninth digit even reveals the fiscal region that issued the number. Runs in your browser.

Dots are fine. Nothing is sent to any server.

Enter a CPF to validate.

CPF validation at signup is part of what I implement in management systems.

Frequently asked

How does CPF validation work?

A CPF has 11 digits, with the last two computed from the first nine using module 11. If the check-digit calculation doesn't match the digits given, the number is invalid.

What does the ninth digit of a CPF indicate?

The tax region that issued the number, not the state where the person lives. Digit 8, for example, corresponds to São Paulo; digit 7 to Rio de Janeiro and Espírito Santo.

This is the pocket version

The tool above solves one calculation. What I do under contract is keep it running inside your system, on your data, with nobody typing anything.