Alphanumeric CNPJ Generator
Generate valid CNPJ numbers for software testing in the new alphanumeric format (2026) or the current numeric one. Correct check digits, with or without the mask, in bulk and with no sign-up.
Format
How many
Punctuation
For testing only
The numbers have valid check digits but are random and do not match real companies registered with Receita Federal. Use them in test, QA and development environments — never to impersonate a real CNPJ.
How it works
How the generator builds a valid CNPJ
A valid CNPJ is not just any number: the last 2 digits are check digits, computed from the first 12. To produce a number that passes validation, the tool first draws the 12-position base and only then computes those 2 digits — never the other way around. In numeric mode the base has only digits; in alphanumeric mode it mixes letters (A–Z) and numbers, like the format Receita Federal adopts from July 2026.
The check digits are computed with modulo 11. Each base character becomes a number (digits are 0–9; letters are the ASCII code minus 48, that is A=17 up to Z=42), is multiplied by a weight from 2 to 9 right to left and summed. The remainder of the sum divided by 11 sets each digit. That is why every number generated here passes our CNPJ Validator and any library that follows the specification.
Use the numbers in test environments only. They are statistically valid but random: they belong to no real company and do not appear in Receita Federal records. They are ideal for filling staging sign-ups, testing form rules and validating tax integrations that already need to accept the new alphanumeric format — without using the CNPJ of a real company.
Learn more
Articles to put this tool to work
CNPJ Alfanumérico: o Novo Formato do CNPJ em 2026
A partir de julho de 2026, novas empresas recebem um CNPJ com letras e números. Entenda o que muda, por que o formato alfanumérico foi criado, como fica a estrutura e o dígito verificador, e o que revisar nos seus sistemas antes da virada.
Como Validar e Calcular o Dígito Verificador do CNPJ
O guia técnico do dígito verificador do CNPJ no formato alfanumérico: o algoritmo do módulo 11, a tabela de conversão dos caracteres (ASCII − 48), um exemplo resolvido passo a passo e código JavaScript pronto para validar numérico e alfanumérico.
FAQ
Frequently asked questions
- How do I generate a valid alphanumeric CNPJ?
- Pick the format (alphanumeric or numeric) and the amount, then click generate. The tool draws the 12-position base and computes the 2 check digits with modulo 11, so every generated number passes any CNPJ validation. You can copy it with or without punctuation.
- Is the generated CNPJ a real company?
- No. The numbers have valid check digits but are random and do not match any company registered with Receita Federal. They are meant to fill test databases, validate forms and stage integrations — never to pose as a real CNPJ.
- What is a CNPJ generator for?
- For development and QA. Software teams use valid test CNPJs to check input masks, validation rules, document issuing and sign-up forms without exposing real company data. With the alphanumeric format arriving in 2026, generating valid samples helps teams prepare their systems before the switch.
- What is the difference between the alphanumeric and numeric CNPJ generated here?
- The numeric one uses only digits across the 14 positions, as today. The alphanumeric one allows letters and numbers in the first 12 positions and keeps the 2 check digits numeric — the format Receita Federal starts issuing for new registrations from July 2026. The check-digit math is the same for both.
- Is the CNPJ generator free?
- Yes, it is 100% free, runs entirely in your browser and needs no sign-up. Generate as many test CNPJs as you need, in bulk, in numeric or alphanumeric format, and copy them one by one or all at once.
