International · Brazil
Brazil CNPJ validator.
Check a 14-character CNPJ, the old all-digit kind or the new one with letters that Receita Federal began issuing on 31 July 2026. Everything runs in your browser.
How it works: each of the first 12 characters becomes its ASCII code minus 48 (letters A to Z become 17 to 42), is multiplied by a weight, and the sum is reduced modulo 11 to get the first check digit. The process repeats with that digit added to get the second.
Inputs
Result
Enter a CNPJ and press Check.
How the CNPJ check digits work
A CNPJ is 14 characters: a 12-character base (8-character root plus 4-character branch order) and two numeric check digits. Until 2026 every character was a digit. Since 31 July 2026 Receita Federal issues CNPJs whose first 12 characters may also include the letters A to Z; the two check digits stay numeric. Existing CNPJs do not change and both kinds are valid side by side.
| Step | What happens |
|---|---|
| 1 | Convert each character to its ASCII code minus 48: digits stay 0-9, A=17, B=18 … Z=42 |
| 2 | Multiply the 12 base characters by the weights 5,4,3,2,9,8,7,6,5,4,3,2 and add them up |
| 3 | Take the sum modulo 11. If the remainder is 0 or 1 the first check digit is 0, otherwise it is 11 minus the remainder |
| 4 | Repeat with the first check digit appended and weights 6,5,4,3,2,9,8,7,6,5,4,3,2 to get the second |
Receita Federal's own worked example is 12.ABC.345/01DE: the first sum is 459, remainder 8, digit 3; the second sum is 424, remainder 6, digit 5, giving 12.ABC.345/01DE-35. The first CNPJ Receita Federal issued in the new format, on 31 July 2026, was 00.000.000/E08G-12, and it passes this check.
CPF is not covered
This tool validates CNPJ only. It does not validate a CPF (the personal number), because we could not confirm the CPF algorithm against a Receita Federal primary document.
Checksum check only, not a registry lookup
A passing result means the characters are internally consistent. It does not confirm the company exists or is active; only Receita Federal can confirm that.
Sources
Receita Federal do Brasil, CNPJ alfanumérico, perguntas e respostas (question 14: check digit calculation and worked example). Receita Federal, Receita Federal gera o primeiro CNPJ em formato alfanumérico (31 July 2026).
Checksum only — not a Receita Federal lookup
This tool checks the modulo 11 check digits entirely in your browser. A checksum-valid result is not proof the CNPJ was ever issued. Nothing you type is transmitted, stored, or logged.