CPF Validator
Quickly check whether a Brazilian CPF (individual tax ID) is structurally valid. The check-digit verification runs in real time in your browser.
Brazil-specific tool. This tool uses Brazilian rules and standards (such as Pix, CPF/CNPJ, INSS/income tax or SAC/PRICE tables).
How the CPF is validated
A CPF has 11 digits, the last 2 being check digits. We compute them with the Module 11 algorithm and compare with the input.
What validation does not do
It is a structural check: it confirms the number is mathematically valid, not whether it is active or belongs to someone. Use official Receita Federal channels for that.
Frequently asked questions
Does a valid CPF mean it exists?
Not necessarily — it means the check digits are correct.
Is data stored?
No, everything runs in your browser.
Does it accept formatted CPF?
Yes, we format it automatically as you type.