tools.junyo.dev

CNPJ Generator

Generate check-digit-valid CNPJ numbers for testing, staging and form validation.

Details below
About this tool

Synthetic CNPJ for development environments.

The generator creates CNPJ numbers that are coherent with the mathematical check-digit rule. It does not query Brazilian government systems, verify registry status or claim that a company exists.

How to use

Generate a test number and copy the needed format.

  1. Click generate again to create another synthetic CNPJ.
  2. Copy either the punctuated format or the fourteen raw digits.
  3. Use it in fixtures, QA, documentation and form validation, never to represent a real company.
Technical limit

Valid CNPJ does not mean active company

A CNPJ can pass the check-digit algorithm and still not exist in any public registry. This tool does not perform registry lookup or promise active status.

Real lookups require a reliable source, cache policy, request limits, timeout and clear messages about data origin.

  • Mathematical validation is client-side.
  • Registry lookup is outside v1.
  • Generated data is for software testing.
FAQ

Frequently asked questions

Not necessarily. It only passes the mathematical check-digit rule.

Brazilian Documents

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