Webkinz are toy stuffed animals that were originally released by the Ganz (Ganz (toy company)) company on April 29, 2005. The toys are similar to many other small plush toys, however, each Webkinz toy has an attached tag with a unique "Secret Code" printed on it that allows access to the "Webkinz World" website. On Webkinz World, the Secret Code allows the user to own a virtual version (digital pet) of the pet for online play for a limited time (one year). To maintain long-term access to an account, the user must continue to purchase additional stuffed toys.

There are also smaller, less expensive versions of the toys called Lil Kinz as well as larger, slightly more expensive versions in the Signature collection launched in early 2009. In June 2008, Ganz opened the Webkinz eStore, where users can buy virtual items such as furniture, clothing, charms, and online-only pets. eStore items can only be used in conjunction with an active Webkinz or Webkinz, Jr. account. In 2009, Birthstone pets were released. One new birthstone pet was released for every month. In April 2010, Ganz replaced the Birthstone pets with the Zaniac Pets and the Zaniac theme, for those who enjoy constellations and stars. Again, one Zaniac pet will be released every month along with its constellation.

Sales of plush Webkinz and Lilkinz are limited to the United States and Canada, however virtual pets can be purchased from the eStore by international residents. Secret Codes issued in conjunction with virtual pets can be used the same way as Secret Codes attached to plush pets.