Finance · free tool

French VAT number generator from SIREN or SIRET

Generate a French VAT number from a valid SIREN or SIRET, then check its local format and key.

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French VAT Generator & Validator

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Generate from SIREN / SIRET Validate a VAT number

SIREN or SIRET numbers

Paste up to 50 valid identifiers. A SIRET is automatically reduced to its 9-digit SIREN.

Generated French VAT numbers

Good to know

A French VAT number contains the FR prefix, a two-digit computer key and the company’s nine-digit SIREN. A 14-digit SIRET contains that SIREN in its first nine digits.

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Understand

Understand French VAT Generator & Validator

What is French VAT Generator & Validator?

A French VAT number contains the FR prefix, a two-digit computer key and the company’s nine-digit SIREN. A 14-digit SIRET contains that SIREN in its first nine digits.

Main use case: Convert one or many SIREN or SIRET identifiers into French VAT numbers, or validate a VAT number before invoicing, CRM import or a VIES check.

Common use cases

SIREN to VAT: Calculate the numeric key and build a French VAT number from a valid SIREN.
SIRET to VAT: Extract the first nine digits of a SIRET and generate the same company VAT number.
Batch CRM preparation: Convert up to 50 identifiers and flag values with invalid length or Luhn checksum.
Invoice QA: Check the FR prefix, VAT key and SIREN before using a value in a test invoice.

How to use the tool

Choose generation from SIREN/SIRET or VAT validation.
Paste one company identifier per line for batch conversion.
Review any invalid SIREN or SIRET values.
Copy the generated French VAT numbers.
Use VIES when you need official intra-EU registration status.

Best practices

Store SIREN, SIRET and VAT numbers as strings.
Distinguish a locally calculated key from official VAT registration.
Keep the FR country prefix in invoices and exports.
Check VIES when an intra-EU transaction requires registration evidence.
Never use synthetic test values on real tax documents.

Common mistakes

Using all 14 SIRET digits: A French VAT number uses the nine-digit SIREN, not the complete SIRET.
Treating a calculation as registration proof: A coherent key does not prove that the business exists or is enabled for intra-EU trade.
Dropping the FR prefix: The complete French VAT identifier starts with FR, followed by the key and SIREN.

FAQ

Frequently asked questions

How do I generate a French VAT number from a SIREN?

Enter the nine-digit SIREN. The tool checks its Luhn checksum, calculates the numeric VAT key and combines FR, the key and the SIREN.

Can a SIRET be converted to a French VAT number?

Yes. The first nine digits of a SIRET are the SIREN used to calculate the company’s French VAT number.

What is the format of a French VAT number?

The common format has 13 characters: FR, a two-digit computer key and the company’s nine-digit SIREN.

Does a generated VAT number prove VAT registration?

No. It proves only local mathematical consistency. The French tax administration assigns VAT numbers and VIES reports intra-EU registration status.

Does this tool query VIES?

No. All calculations run locally in the browser. Use the European Commission’s VIES checker for official intra-EU status.

Can I convert several SIREN or SIRET values at once?

Yes. Paste one identifier per line to convert up to 50 values in one batch.

Why is a SIREN or SIRET rejected?

The tool rejects identifiers with the wrong length, an invalid Luhn checksum or an invalid extracted SIREN.

Can I generate a French VAT number for QA?

Yes, starting from a coherent synthetic SIREN. Never present the result as an officially assigned tax number.

Are my inputs sent to a server?

OnSubmit tools run in the browser whenever the task can be processed locally. Avoid pasting production secrets, real banking details or personal data into public tools.