format-number.js

;(function($) {
  /**
   * Formats a given number (or number as a string)
   *
   * @param {Number|String} num
   * @param {Object} [userOpts] User configuration
   * @returns {String|Boolean}
   */
  var formatNumber = function(num, userOpts) {
      var defaults = {
          decimals: 2,
          prefix: '',
          suffix: '',
          separator: {
              decimal: ',',
              thousand: '.'
          }
      }, opts;
  
      userOpts = userOpts || {};
      opts = $.extend({}, defaults, userOpts);
  
      // Cast the string to a number
      if(typeof(num) === 'string') {
          num = 1 * num;
      }
      if(!isFinite(num)) {
          return false;
      }
      num = num.toFixed(opts.decimals);
  
      // Replace the dot
      num = num.replace(/\./, opts.separator.decimal);
  
      // Set the thousand separator
      num = num.replace(/\B(?=(\d{3})+(?!\d))/g, opts.separator.thousand);
      num = opts.prefix + num + opts.suffix;
  
      return num;
  };
})(jQuery);