CNPJ Generator
🛡️ Tools for educational and development purposes. Inappropriate use is the user's responsibility.Generate valid CNPJ numbers (numeric and alphanumeric) for testing
About this tool
The CNPJ generator creates valid Brazilian company registration numbers for testing, both in the traditional numeric format and in the new alphanumeric CNPJ adopted by Receita Federal for registrations from July 2026 (IN RFB 2,229/2024).
It's useful for testing company sign-ups, invoicing, tax integrations and form validation — and for making sure your system already accepts letters in the first 12 positions.
How to use
- A valid numeric CNPJ is generated when the page opens.
- Choose Alphanumeric CNPJ to test the new format with letters.
- Toggle the mask (00.000.000/0000-00) and copy.
- Use Bulk generate to get several at once.
Frequently asked questions
What is the alphanumeric CNPJ?
It's the new format defined by Receita Federal: the first 12 positions may contain letters and digits, while the 2 check digits remain numeric. Existing CNPJs don't change.
How is the alphanumeric check digit calculated?
Each character is converted to its ASCII code minus 48 (so '0'–'9' are 0–9 and 'A' is 17) and goes through the same modulo-11 calculation with the numeric CNPJ weights.
Can I use it on real invoices?
No. The numbers are for testing only.
How do I validate a CNPJ I received?
Use the CPF & CNPJ Validator, which supports both formats and explains why a number is invalid.