REGON Generator

What Is a REGON Number?

REGON is the statistical identification number GUS (Główny Urząd Statystyczny), Poland’s Central Statistical Office, assigns to every registered business entity. It is one of three core Polish business identifiers, alongside NIP (tax) and KRS (court register). For the full explainer, including what REGON stands for, how it differs from NIP and KRS, and how to look one up, see the REGON Validator.

How the REGON Number Generator Works

This REGON generator creates random numbers with a valid check digit. It supports both 9-digit and 14-digit formats. Every generated number is fictitious and safe for use in testing environments.

Pick a format, click generate, and copy the result. You can produce a single number or a batch. The tool is free and requires no sign-up.

Developers use generated REGON numbers for software testing, QA pipelines, form validation, and training systems. If you need test data for other Polish identifiers, see the NIP Generator and PESEL Generator.

REGON Number Format: 9-Digit vs 14-Digit

A standard REGON number has 9 digits. The first 8 identify the entity. The 9th is a check digit calculated using a weighted modulo-11 algorithm.

The 14-digit REGON identifies a local unit: a branch, office, or subsidiary. The first 9 digits match the parent entity’s REGON number. Digits 10 through 13 form a sequential identifier for the local unit. The 14th digit is another check digit.

Both formats follow the same validation logic. The check digit confirms the number was not mistyped or fabricated. Developers building Polish business forms often validate REGON input by recalculating this digit.

Check Digit Weights

The 9-digit REGON uses weights 8, 9, 2, 3, 4, 5, 6, 7. Multiply each of the first 8 digits by its weight, sum the products, and take the result modulo 11. If the remainder is 10, the check digit is 0.

The 14-digit REGON uses weights 2, 4, 8, 5, 0, 9, 7, 3, 6, 1, 2, 4, 8 for the first 13 digits. The same modulo-11 rule applies.

How to Verify a REGON Number

This page generates fictitious REGON numbers for testing. To check whether a real REGON belongs to a registered entity, search the GUS Wyszukiwarka REGON at wyszukiwarkaregon.stat.gov.pl. For a quick check of the check digit alone, use the REGON Validator.

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