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Brazil CPF Generator & Validator

Generate valid test CPF numbers (Cadastro de Pessoas Físicas) by fiscal region — or paste a CPF to check its region and Receita Federal check digits.

CPF Generator

Choose a fiscal region, or leave it random. The base number is random; the region digit is set from your choice and both check digits are calculated with Receita Federal's modulo-11 formula.

Flag of Brazil

Brazil · 11 digits

The 9th digit of the CPF

1 – 100

CPF Validator

Paste an 11-digit CPF, with or without punctuation, to check its fiscal region and check digits.

Every CPF this tool produces is synthetic test data only. It is not issued by Receita Federal, is not registered against any person, and does not belong to any real resident of Brazil. Use it on your own test systems only — never to complete a real application, verification or KYC check.

How a CPF number is structured

A CPF is 11 digits, and unlike South Africa's ID number it encodes no date of birth — just a sequentially assigned base number, the issuing fiscal region, and two check digits. Taking 113.951.678-77 as an example:

The segments of an 11-digit Brazilian CPF
DigitsSegmentMeaning
11395167Base numberAn individually assigned sequential number — eight digits.
8Fiscal regionThe Receita Federal region the CPF was issued in — 8 is São Paulo.
77Check digitsTwo digits, each a weighted-sum checksum computed modulo 11 over the digits before it.

Because the checksum is the only thing tying the number together, validation rules focus entirely on it — plus one deliberate exception: the ten repdigit numbers (000.000.000-00 through 999.999.999-99) satisfy the checksum formula by coincidence, so every real validator, and this one, rejects them outright.

Why generate test CPFs?

Any system that accepts a CPF needs realistic data to test against — bank and fintech onboarding, telecom and SIM registration, e-commerce checkouts, and the KYC and AML checks behind all of them.

Using a real person's CPF in a test environment is a privacy risk under Brazil's data protection law (LGPD). Synthetic CPFs that are structurally valid let you exercise the same code paths — format checks, region derivation, checksum validation — without any real personal information ever entering your test systems.

Frequently asked questions

What is a CPF?
CPF (Cadastro de Pessoas Físicas) is the 11-digit taxpayer registry number the Receita Federal issues to identify individuals in Brazil. It is required for almost everything — opening a bank account, signing a mobile contract, filing taxes, making purchases above certain thresholds.
Is a CPF the same as a CNPJ?
No. A CPF identifies an individual person; a CNPJ (Cadastro Nacional da Pessoa Jurídica) is the equivalent 14-digit registry number for a company, calculated with a different checksum. This tool generates CPFs only.
How is a CPF structured?
The first eight digits are an individually assigned base number. The ninth digit identifies the fiscal region the CPF was issued in — for example 8 for São Paulo or 6 for Minas Gerais. The last two digits are check digits, each a weighted-sum checksum computed modulo 11.
Why does the validator reject numbers like 111.111.111-11?
Because every digit is identical, a repdigit CPF happens to satisfy the checksum formula — but Receita Federal's own validation rules explicitly reject all ten repdigit numbers (000.000.000-00 through 999.999.999-99) regardless. This tool rejects them too, and never generates one.
Are these real CPFs?
No. Every CPF this tool produces is randomly generated test data that happens to be structurally valid and pass the checksum. The numbers are not issued by Receita Federal and do not belong to any real person. Never use them to impersonate anyone or to complete a real application.
How do I validate a CPF?
Check that it is exactly 11 digits, that it is not one of the ten blacklisted repdigit numbers, and that both check digits match the weighted modulo-11 formula over the digits before them. The validator on this page performs all three checks and shows you which one failed.
Why would I need generated CPFs?
To test software without touching real personal data. Bank and fintech onboarding, telecom and SIM registration, e-commerce checkouts and KYC/AML checks in Brazil all need realistic CPF input, and synthetic numbers keep real personal information out of your test environments.