how Brazil's CNPJ company number works
A CNPJ identifies a company before Brazil's Receita Federal, and each stretch of the number has a fixed role: root, establishment order and check digits. This page explains that structure, what changes with the alphanumeric CNPJ, and what a public lookup actually returns, before you search a CNPJ in the tool.
The first 12 characters go through modulo 11 with weights 5 down to 2 repeating for the first digit, and 6 down to 2 (including the first digit just calculated) for the second; the result closes at 91 for this specific base.
0001 confirms this is the headquarters, not a branch; the ACTIVE status and the CNAE for 'multiple banks with a commercial portfolio' come from the public registry, not from the check-digit math.
The letter A has ASCII code 65; the Receita's rule subtracts 48 and uses 17 as the value multiplied into the sum, the same treatment given to any other letter allowed in an alphanumeric CNPJ.
You can usually review registry data such as legal name, trade name, status, address, opening date, economic activity and sometimes ownership or management information. The exact scope depends on the source and on field availability at the time of lookup.
It flags that establishment as the company headquarters; following numbers like 0002 or 0003 identify branches that share the same 8-digit root, but carry their own check digits because the calculation runs over the full 12 characters.
The rule took effect through Instrução Normativa RFB 2.229/2024, for new registrations as the Receita exhausts purely numeric combinations; the check digits stay numeric, and the calculation treats each letter as its ASCII code minus 48.
No. Modulo 11 only confirms the check digits match the root and the order, something any synthetic CNPJ generator reproduces; knowing whether the company exists and what its registration status is requires the public registry lookup, not just validating the number.
In the Receita Federal's public registry lookup, which returns the legal name, registration status (active, shut down, suspended, unfit or void), main CNAE code and start-of-activity date; that is the registry the tool queries, not just the check-digit calculation.
Legal name, status, activity, address and ownership of a company.
We validate the digits before the lookup and lay everything out in readable cards.
Looked up in real time through J-Kit's secure backend, with validation, timeout and rate limiting. Nothing is stored on your device. Source: official Brazilian public data.