firstImpression.js

firstImpression is a JavaScript micro-library that answers the question, "Has this visitor been here before?" It's mostly a wrapper for a plain JS port of jquery.cookie. No other libraries required.

firstImpression() returns true for a new user, false for a returning user. Calling firstImpression() also sets a cookie if one does not already exist. The default cookie name is _firstImpression and the default expiration is 2 years (730 days).

Usage

// Basic usage
if ( firstImpression() ) {
  console.log('New user');
}

// Specify cookie name
if ( firstImpression('foo') ) {
  console.log('New user');
}

// Specify cookie name and expiration in days
if ( firstImpression('foo', 365) ) {
  console.log('New user');
}

Removing cookies

// Remove default cookie
firstImpression(null);

// Remove custom named cookie
firstImpression('foo', null);

Browser Support

This should work in any browser that supports cookies. Tested in Chrome, Firefox, Opera, IE6-10, iOS, Android, and Opera Mobile.

Contact

@robflaherty

License

Licensed under the MIT and GPL licenses.