🏢Company & VAT Number Validator

Company & VAT number validator — check NIP, SIREN, EU VAT online

Our free company number validator lets you instantly check a business identification number or a VAT number. From the dropdown you choose the number type: the Polish NIP, the French SIREN/SIRET, the Norwegian organisasjonsnummer, the Danish CVR, the Finnish Y-tunnus, or an EU VAT number. The tool verifies the length, format and checksum according to each country's official algorithm and shows the result with details in a fraction of a second.

The EU VAT option detects the country automatically from the two-letter prefix of the number (e.g. DE, PL, FR) and works for all 27 member states. Where we know the algorithm, we also check the checksum; otherwise we verify the format and clearly say so. Bear in mind that a valid number does not guarantee that the company is active or registered for VAT.

Full privacy — local processing

Verification takes place entirely in your browser — not a single character of the entered number is sent to any server. We do not check registration in the VIES system; confirming an active VAT number requires the official European Commission lookup. You can use the validator even offline.

Frequently asked questions

Which company numbers does this validator check?

The tool verifies the Polish NIP, the French SIREN and SIRET, the Norwegian organisasjonsnummer, the Danish CVR number, the Finnish Y-tunnus, and EU VAT numbers from all 27 member states. You pick the number type from the dropdown in the first field — the labels and examples adapt automatically.

How does EU VAT number validation work?

The validator detects the country from the two-letter VAT prefix (e.g. DE, PL, FR), checks whether the format matches that country's pattern, and then — where the algorithm is known — verifies the checksum. For some countries the checksum is not publicly documented, so only the format is checked; in that case the result shows a note that the checksum was not verified.

What is the difference between SIREN and SIRET?

SIREN is a 9-digit identifier of a French company, while SIRET is a 14-digit establishment number — it consists of the 9-digit SIREN plus a 5-digit NIC code that identifies a specific establishment. The validator recognises both formats automatically by length and shows the breakdown of a SIRET into its SIREN and NIC.

Does a valid VAT number mean the company is registered?

No. We only check the format and checksum offline — we do not verify registration in the European Commission's VIES system. A number may be mathematically valid yet inactive or not assigned to any company. To confirm registration, use the official VIES lookup.

Is my data sent to a server?

No. All verification is performed locally in your browser — not a single character of the entered number reaches any server. You can check a company number even without an internet connection.