Best Free Online Developer Tools to Use in 2026
A practical, opinionated list of the best free online developer tools worth using in 2026, organized by category so you can find what you need fast.
Aug 08, 2026
VAT Number Validator
Validate European VAT numbers with format checksum verification for all EU member states.
VAT Number Validator
Enter a VAT number with or without the country prefix. Select a country for targeted validation.
Country
-
Country Code
-
Format
-
Checksum
-
- Select country — Choose an EU country from the dropdown.
- Enter VAT number — Type the VAT number with or without the country prefix (e.g. GB123456789 or 123456789).
- Instant validation — See format validation, expected pattern, and checksum result.
What Is a VAT Number?
A VAT (Value Added Tax) identification number is a unique identifier used by businesses in the European Union for tax purposes. Each EU member state has its own format with a two-letter country prefix followed by a variable-length numeric code.
VAT numbers are essential for cross-border trade within the EU and are used for:
- Identifying businesses for VAT purposes
- Validating transactions on invoices
- Claiming VAT refunds on business expenses
- Verifying EU trading partners
EU VAT Format Reference
| Country | Prefix | Format | Length |
|---|---|---|---|
| Austria | AT | U12345678 | 9 |
| Belgium | BE | 1234567890 | 10 |
| Bulgaria | BG | 123456789 | 9-10 |
| Croatia | HR | 12345678901 | 11 |
| Cyprus | CY | 12345678X | 9 |
| Czech Republic | CZ | 123456789 | 8-10 |
| Denmark | DK | 12345678 | 8 |
| Estonia | EE | 123456789 | 9 |
| Finland | FI | 12345678 | 8 |
| France | FR | 12345678901 | 11 |
| Germany | DE | 123456789 | 9 |
| Greece | EL | 123456789 | 9 |
| Hungary | HU | 12345678 | 8 |
| Ireland | IE | 1234567X | 8-9 |
| Italy | IT | 12345678901 | 11 |
| Latvia | LV | 12345678901 | 11 |
| Lithuania | LT | 123456789 | 9-12 |
| Luxembourg | LU | 12345678 | 8 |
| Malta | MT | 12345678 | 8 |
| Netherlands | NL | 123456789B01 | 12 |
| Poland | PL | 1234567890 | 10 |
| Portugal | PT | 123456789 | 9 |
| Romania | RO | 1234567890 | 10 |
| Slovakia | SK | 1234567890 | 10 |
| Slovenia | SI | 12345678 | 8 |
| Spain | ES | X12345678 | 9 |
| Sweden | SE | 123456789012 | 12 |
| United Kingdom | GB | 123456789 | 9-12 |
What is a VAT number used for?
A VAT number is used to identify businesses for VAT (Value Added Tax) purposes within the European Union. It's required for cross-border transactions and invoicing.
How do I find a company's VAT number?
VAT numbers are typically displayed on invoices. You can also use the EU's VIES (VAT Information Exchange System) online portal to verify a company's VAT number.
What is VIES?
VIES (VAT Information Exchange System) is the European Commission's online system for verifying VAT numbers across EU member states. This tool validates format only; use VIES for real-time registration checks.
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