All Kellogg's products contain UPC codes, but products that are part of the Kellogg's Family Rewards program also have a specially-printed code on the inside of the box. These codes can be entered online to enter sweepstakes, print coupons or get gift cards and other special rewards.
As of March 2015, Kellogg's Family Rewards codes can be found on over 500 different products. To redeem codes, users need to create a free account at the Kellogg's Family Rewards website. Codes can also be entered via text message. Up to 20 codes can be entered per user each day, though a user can have only one Kellogg's Family Rewards account.