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NIF Generator (test data)

NIF Generator: test data only

Generates fictitious tax numbers with a valid check digit, to fill test environments without using real people’s data. These numbers are not real.

By Elijah·UPDATED JULY 2026·2 MIN·OFFICIAL SOURCES
KEY FACTS
Format
9 digits, the last a mod-11 check digit
First digit
1–3 individual, 5 company (you choose)
Per batch
1 to 20 numbers
Nature
Fictitious, software testing only
ParticularEmpresa
−5+
RESULTADO

    How this works

    The generator picks a first digit by type (individual or company), fills the next digits at random, and computes the ninth (the check digit) with the same modulo-11 formula the AT (tax authority) uses. The result passes any NIF validator, but is purely fictitious.

    1. 1
      Pick the type and how many
      "Individual" makes numbers starting with 1, 2 or 3; "Company" with 5. You can ask for 1 to 20 at a time.
    2. 2
      The generator computes the check digit
      The next seven digits are random. The ninth comes from the mod-11 formula: multiply the first eight by weights 9 down to 2, add up, and the digit is 11 minus the remainder of dividing by 11 (10 or 11 count as 0).
    3. 3
      Copy into your test environment
      Copy one number at a time or the whole list. The numbers pass any NIF validator, including ours.
    4. 4
      Use them for testing only
      These NIFs belong to no one and should never leave the test environment. Using a NIF that was not assigned to you to identify yourself to third parties or the State is forgery and a crime.

    Frequently asked

    Are these NIFs real?
    No. They are random numbers that only satisfy the check-digit formula. They are meant for testing forms, databases and integrations. They do not correspond to real taxpayers and must not be used as if they did.
    What is a NIF generator for?
    Developers and QA teams need well-formed NIFs to fill test environments without using real people’s data. Generating fictitious but structurally valid numbers avoids exposing personal data during development.
    Can I use one of these to open an account or sign a contract?
    No. Using a NIF that was not assigned to you (even a randomly generated one) to identify yourself to third parties or the State is forgery and a crime. These numbers exist only for technical testing.
    How is the first digit chosen?
    You pick the type: "Individual" starts with 1, 2 or 3; "Company" starts with 5. The remaining digits are random and the last is the modulo-11 check digit.
    OFFICIAL SOURCES
    DISCLAIMER
    The generated numbers are fictitious and intended solely for software testing. They belong to no one and may, by coincidence, match a real NIF. Using a NIF that was not assigned to you to identify yourself to third parties or the State is forgery and punishable by law.