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

``bash
npm install validator-tax-id


or

yarn add validator-tax-id

or

pnpm add validator-tax-id
`

Usage

$3

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

`typescript
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)
`

$3

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

`typescript
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
`

$3

If you don't know the specific document type:

`typescript
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

$3

- 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