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tin-validator

v2.1.0

Published

Taxpayer Identification Number validator and masker

Readme

tin-validator

Validate and mask Taxpayer Identification Number (TIN) from US and EU countries. A TIN may be an Employer Identification Number (EIN), an Individual Taxpayer Identification Number (ITIN) or a Social Security number (SSN).

Most of the functions default to US country as you can see in the documentation below. Also for US country, entityType is not required. When trying to validate EU TIN we need to set both paramenters country and entityType as TIN format varies from ech country and entity types.

For EU TIN validation, we first try to validate by using an online API provided by the European Commisision, if any error is received from this API (for example, if the API is down), then we run our internal validations instead.

Status

npm version build status

Installation

Install the package via npm:

npm install tin-validator --save

Usage

isValid(value)

This method validates if the given value is a valid Taxpayer Identification Number.

Arguments

  • value (*): The string value to validate.
  • options (object, optional):
    • country (string, optional): Country of document to validate (by default, US).
    • entityType (string, optional): Possible values: natural-person and legal-entity. By default: natural-person.

Returns

(boolean): Returns whether the input value is a valid TIN or not.

Example

isValid({});
// => false

isValid('9-0-0700000');
// => false

isValid('900-70-0000');
// => true

isValid('900700000');
// => true

isValid('123456789', { country: 'PT', entityType: 'natural-person' });
// => true

mask(value)

This method will help you protect this sensitive piece of information by obfuscating some digits.

Arguments

  • value (*): The value to mask.
  • options (object, optional):
    • country (string, optional): Country of document to mask (by default, US).
    • entityType (string, optional): Regulation entity type (by default, natural-person).

Returns

(string): Returns the masked value by replacing value certain digits by 'X'.

Example

mask({});
// Throws an Error.

mask('9-0-0700000');
// Throws an Error.

mask('900-70-0000');
// => XXX-XX-0000

mask('900700000');
// => XXXXX0000

sanitize(value)

This method will remove all non numeric characters from the value.

Arguments

  • value (*): The value to sanitize.
  • options (object, optional):
    • country (string, optional): Country of document to sanitize (by default, US).
    • entityType (string, optional): Regulation entity type (by default, natural-person).

Returns

(string): Returns the sanitized value containing only numeric characters.

Example

sanitize('9-0 0700000');
// => 900700000

sanitize('900a7#$0foobar0000');
// => 900700000

Tests

To test using a local installation of node.js:

npm test

Release process

The release of a version is automated via the release GitHub workflow. Run it by clicking the "Run workflow" button.

Upgrading from version 1 to version 2

The methods on version 1 are the same as on version 2. The only change is that the methods were sync, while now they are async.

License

MIT