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CUIT and CUIL calculator

Get the CUIT or CUIL for an Argentine DNI number, including the switch to type 23 when ARCA's rule needs it, or check a CUIT's digit in your browser.

CUIT / CUILClave Única de Identificación Tributaria / Laboral

Tax and labour identification number · written like 20-12345678-6

Where the rules come from

CUIT or CUIL from a DNI number

Type

Or add the check digit to the first 10 digits

Runs in your browser · no uploadHow it works

How to use CUIT calculator

  1. 1

    Type the DNI number

    The page opens on the calculator. Enter the 7 or 8 digits of the DNI, with or without dots.

  2. 2

    Choose the type

    Pick 20, 27 or 30 for a company; the result switches to 23 or 33 on its own when ARCA's rule requires it.

  3. 3

    Copy the CUIT or CUIL

    The number appears in the usual 20-12345678-6 form with a copy button and the fields it contains.

  4. 4

    Validate a list

    On the Check tab paste CUITs or CUILs one per line to find the wrong ones and the digit each should end in.

Limits and Pro

Free: CUIT and CUIL from any 7- or 8-digit DNI, checks of up to 10,000 pasted CUITs, and test batches of up to 10,000.

Pro is ad-free; there is nothing else to unlock. See Pro

About CUIT calculator

In Argentina a worker's CUIL and a taxpayer's CUIT share one format: two digits for the type, the eight digits of the DNI (or a company number), and a check digit. That is why an employer, an accountant or an online shop can usually work out someone's CUIL from their DNI, and why a form that asks for it refuses a number whose last digit is off.

The calculator takes the DNI number and the type. For people the usual types are 20 and 27, traditionally used for men and women, and 30 for companies. The first ten digits are multiplied by 5, 4, 3, 2, 7, 6, 5, 4, 3 and 2; the check digit is 11 minus the remainder of the sum divided by 11, and a result of 11 becomes 0. When the result would be 10 no digit works, so ARCA changes the type instead: a person gets 23, with check digit 9 for a former 20 and 4 for a former 27, and a company gets 33. The page applies that switch automatically and says when it has.

Paste existing CUITs on the Check tab to validate a list: each one shows its type, the DNI or entity number inside it, and the digit it expected. The Generate tab makes test CUITs and CUILs for people or companies.

A correct check digit does not mean the number is registered with ARCA or ANSES, or that it belongs to the person you think; this page never queries the official padrón.

Privacy

The DNI numbers you type and the CUITs you paste are worked out by this page in your browser and never sent to ARCA, ANSES or any other server. Nothing is saved once you close the page.

CUIT calculator: frequently asked questions

How do I get a CUIL from a DNI number?
Put the type in front of the eight DNI digits, 20 or 27 for people, and add the check digit: weights 5, 4, 3, 2, 7, 6, 5, 4, 3, 2, then 11 minus the remainder of the sum by 11. For DNI 12345678 with type 20 the sum is 148, the remainder 5, so the CUIL is 20-12345678-6.
Why does my CUIT start with 23 instead of 20 or 27?
For some DNI numbers the calculation with 20 or 27 ends at 10, which is not a digit. In that case ARCA keeps the DNI and changes the type to 23, and the check digit then comes out as 9 for those who would have had 20 and 4 for 27. Companies whose type 30 gives 10 get 33 the same way.
What is the difference between a CUIT and a CUIL?
Both are eleven digits built the same way. The CUIL identifies a person in the labour and social security system and is assigned by ANSES; the CUIT identifies a taxpayer at ARCA, the former AFIP, and is needed to invoice or register a business. A person who starts working on their own usually keeps the same number as CUIT.
Does the type digit show whether the holder is a man or a woman?
Only traditionally: 20 has been used for men and 27 for women, but type 23 covers both, and the type follows the rule above rather than saying anything about the person. Treat the type as part of the number, not as data about its holder, and never infer someone's gender from it.
Does a correct check digit mean the CUIT is registered?
No. The check digit only proves the eleven digits are consistent with each other; many valid-looking CUITs were never assigned. To confirm that a CUIT exists and see the holder's tax status you need ARCA's public constancia de inscripción, which this page never queries.

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