eu-tax-id-validator

Validate European tax IDs (VAT numbers, NIF, CIF) with format checks and checksum verification. Zero dependencies, < 5KB minified.

Supports 30 countries: 27 EU member states + United Kingdom, Norway, and Switzerland.

Install

npm install eu-tax-id-validator

Quick Start

import { validateTaxId, detectCountry, formatVatNumber } from 'eu-tax-id-validator';

// Validate with checksum
validateTaxId('PT502011378');
// { valid: true, country: 'PT', normalized: 'PT502011378', checksum_verified: true }

// Auto-detect country
detectCountry('502011378');
// 'PT'

// Format for display
formatVatNumber('PT502011378');
// 'PT 502 011 378'

API

`validateTaxId(raw: string): ValidationResult`

Validates a tax ID / VAT number. Cleans input (removes spaces, dashes, dots), auto-detects country, and runs format + checksum validation.

interface ValidationResult {
  valid: boolean;
  country: string | null;
  normalized: string;        // Cleaned, uppercase, with country prefix
  checksum_verified: boolean; // true if checksum algorithm verified
  error?: string;
}

`detectCountry(taxId: string): string | null`

Detects country from a tax ID. Tries 2-letter prefix first, then format-based detection.

`formatVatNumber(taxId: string, country?: string): string`

Formats a tax ID with country-specific grouping for display.

Country	Input	Output
PT	`PT502011378`	`PT 502 011 378`
DK	`DK10150817`	`DK 10 15 08 17`
GB	`GB123456789`	`GB 123 4567 89`
DE	`DE123456789`	`DE 123 456 789`
PL	`PL7740001454`	`PL 774-000-14-54`
FI	`FI01234562`	`FI 0123456-2`
CH	`CH105835786`	`CH 105.835.786`

`isEUMember(countryCode: string): boolean`

Returns true if the country is an EU member state.

`COUNTRIES`

Object with metadata for all 30 supported countries:

COUNTRIES['PT']
// { code: 'PT', name: 'Portugal', local_name: 'Portugal',
//   tax_id_name: 'NIF', eu_member: true, has_checksum: true,
//   format_description: '9 digits with Modulo 11' }

Supported Countries

Full checksum validation (7 countries)

Country	Tax ID	Algorithm
PT Portugal	NIF	Modulo 11
DK Denmark	CVR	Modulo 11
NO Norway	Org.nr	Modulo 11
FI Finland	Y-tunnus	Modulo 11
PL Poland	NIP	Weighted checksum
CZ Czech Republic	IČO	Modulo 11
CH Switzerland	UID	Modulo 11

Format validation (23 countries)

AT, BE, BG, CY, DE, EE, EL (Greece), ES, FR, GB, HR, HU, IE, IT, LT, LU, LV, MT, NL, RO, SE, SI, SK

Features

Zero dependencies — pure TypeScript, no runtime deps
Dual format — ESM and CommonJS
Tree-shakeable — import only what you need
Tiny — < 5KB minified
Type-safe — full TypeScript types exported
30 countries — 27 EU + UK, Norway, Switzerland
Checksum verification — Modulo 11 and weighted checksums for 7 countries
Input cleaning — handles spaces, dashes, dots, lowercase

Going Beyond Validation

Need live company data — name, address, legal form, directors, VAT status?

VeriCorp API enriches tax IDs with real-time data from official registries across Europe. 8 countries with full enrichment, 27 with VAT validation.

// Local validation (this package)
validateTaxId('PT502011378');
// { valid: true, country: 'PT', checksum_verified: true }

// Live enrichment (VeriCorp API)
// → name: "Nexperience Lda", status: "active", address: "...", legal_form: "Lda", ...

Get your free API key →

License

MIT