Brazil CPF Validator
Validate Brazilian CPF numbers with format checks, checksum explanation, and random generation.
Brazil CPF Validator
Validate Brazilian CPF numbers with format checks, checksum explanation, and random generation.
About the Brazil CPF validator
CPF structure and repeated-digit guard
A CPF has eleven digits. The validator removes punctuation, formats complete numbers as 000.000.000-00, rejects all-identical digit sequences, and shows the region digit that is part of the public CPF structure.
Two check digits, not an official lookup
The two verifying digits are recalculated with the 10-to-2 and 11-to-2 weight sequences. Random CPFs can optionally keep a chosen region digit, but validation stays inside the browser and does not query Receita Federal or confirm a real person's registration. The entered CPF can be reflected in the share URL, so copy links only with sample values.
FAQ
Common questions and answers about this topic.
Can I generate a valid Brazilian CPF with this tool?
Yes. It creates numbers with correct check digits (the official weighted-sum rule) for testing and development. You can fix the region digit or leave everything random.
Is it legal to use a generated CPF?
Only for software testing, sample forms, or learning. The numbers do not correspond to real people and must not be used for impersonation or any unlawful purpose.
How are the CPF check digits calculated?
The first nine digits are multiplied by descending weights and divided by eleven; the remainder determines the tenth digit, then the process repeats including that digit for the eleventh. The tool shows each step.
Is my data sent to any server?
No. All validation and generation happen in your browser — nothing is uploaded or stored.