The CUIT/CUIL Generator creates Argentine Clave Única de Identificación Tributaria (companies) or Laboral (individuals) numbers, with the check digit computed via AFIP's modulo-11 algorithm — AFIP having been succeeded by ARCA (Agencia de Recaudación y Control Aduanero), created by Decree 953/2024.
What it is
The CUIT/CUIL has 11 digits: 2 prefix digits (indicating the taxpayer type — 20 for men, 27 for women, 30 for companies), 8 digits of the number (usually the national ID, for individuals), and 1 final check digit. That digit comes from multiplying the first 10 digits by weights descending from 5 to 2 and then from 7 to 2, summing everything, and taking the remainder of dividing by 11.
This tool generates fictitious CUIT/CUIL numbers that pass that check, with two options:
- Individual: prefix 20 or 27, with 8 random digits.
- Company: prefix 30.
Neither belongs to a real person or company — they exist only to test systems.
How to use it
Pick the type (individual or company) and quantity, click Generate CUIT/CUIL, and copy or download the result. To check an existing number, use the Validator tab.
How the check digit is calculated
Multiply the first 10 digits (prefix + number) by the weights 5, 4, 3, 2, 7, 6, 5, 4, 3, 2, in order, and sum everything. The check digit is 11 minus the remainder of dividing that sum by 11 — with the caveat that a remainder of 1 has no single-digit solution under the most commonly cited conventions, so this tool simply draws another 8-digit number when that happens, avoiding the ambiguous case entirely.
Worked example
For prefix 20 and number 12345678, multiplying by 5,4,3,2,7,6,5,4,3,2: 2×5+0×4+1×3+2×2+3×7+4×6+5×5+6×4+7×3+8×2 = 148. Dividing by 11, the remainder is 5, and the check digit is 11−5 = 6. The full CUIT is 20-12345678-6.