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