Tax ID Validator

A lightweight, zero-dependency, and universal TypeScript library to validate Tax IDs (Identification Numbers)

It uses precise mathematical algorithms to verify the integrity of the document number and follow guides of the country governments

Supported Countries

| Country | Code | Documents Supported | Algorithm | | ----------- | ---- | ------------------------------ | ------------------ | | 🇪🇸 Spain | es | DNI, NIE, CIF | Module 23 | | 🇵🇹 Portugal | pt | NIF (Personal) | Module 11 | | 🇫🇷 France | fr | SIREN, SIRET, NIR | Luhn + Mod.97 | | 🇩🇪 Germany | de | SteuerIdNr, VAT Number, W-IdNr | ISO 7064 Mod 10,11 |

Features

• 🚀 Lightweight: Zero external dependencies.
• 🔒 Type-Safe: Written in TypeScript with full type definitions.
• 🌍 Universal: Works in Node.js, React, Vue, Next.js, and Browsers (Legacy Script Tag).
• ⚡ Tree-shakeable: Only import what you need (if using advanced exports).

Installation

npm install validator-tax-id
# or
yarn add validator-tax-id
# or
pnpm add validator-tax-id

Usage

Basic Usage

The main function validateIdentification takes two arguments: the country code (ISO 3166-1 alpha-2) and the value to validate.

import { validateIdentification } from "validator-tax-id";

// 🇪🇸 Spain (ES)
validateIdentification("es", "12345678Z"); // true (DNI)
validateIdentification("es", "X1234567L"); // true (NIE)
validateIdentification("es", "A58818501"); // true (CIF)

// 🇵🇹 Portugal (PT)
validateIdentification("pt", "232013969"); // true (NIF)

// 🇫🇷 France (FR)
validateIdentification("fr", "443061841"); // true (SIREN)

// 🇩🇪 Germany (DE)
validateIdentification("de", "86095742719"); // true (SteuerIdNr)
validateIdentification("de", "DE136695976"); // true (VAT Number)

Individual Validators (Recommended) ✨

For better tree-shaking and direct access, use individual validators:

import {
  // Spain
  validateDNI,
  validateNIE,
  validateCIF,
  // France
  validateSIREN,
  validateSIRET,
  validateNIR,
  // Portugal
  validateNIF,
  // Germany
  validateSteuerIdNr,
  validateVatNumber,
  validateWidnr,
} from "validator-tax-id";

// 🇪🇸 Spain - Direct validation
validateDNI("12345678Z"); // true
validateNIE("X1234567L"); // true
validateCIF("A58818501"); // true

// 🇫🇷 France - Direct validation
validateSIREN("443061841"); // true
validateSIRET("44306184100047"); // true
validateNIR("188057512301180"); // true

// 🇵🇹 Portugal - Direct validation
validateNIF("123456789"); // true

// 🇩🇪 Germany - Direct validation
validateSteuerIdNr("86095742719"); // true
validateVatNumber("DE136695976"); // true
validateWidnr("136695976"); // true

Country Auto-detect

If you don't know the specific document type:

import {
  validateES,
  validateFR,
  validatePT,
  validateDE,
} from "validator-tax-id";

validateES("12345678Z"); // true (auto-detects DNI)
validateES("A58818501"); // true (auto-detects CIF)
validateFR("443061841"); // true (auto-detects SIREN)
validatePT("123456789"); // true
validateDE("86095742719"); // true (auto-detects SteuerIdNr)
validateDE("DE136695976"); // true (auto-detects VAT Number)

API Reference

validateIdentification(country, value)

• country: CountryCode ('es' | 'pt' | 'fr' | 'de') - The ISO code of the country.
• value: string - The document string to validate.
• Returns: boolean (true if valid, false otherwise).

Note: The validator sanitizes the input automatically (removes spaces, hyphens, and is case-insensitive).

Support

If this library helped you, consider buying me a coffee ☕

License

MIT