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.

Install the package via npm:

npm install tin-validator --save

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

• 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.

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

isValid({});
// => false

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

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

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

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

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

• 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).

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

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

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

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

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

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

• 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).

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

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

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

To test using a local installation of node.js:

npm test

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

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.

MIT