ZhuZhu Pets were created by Russ Hornsby for his St. Louis company, Cepia LLC. The name comes from Mandarin zhūzhū (Chinese: 猪猪), meaning "little pig." In late 2009 Cepia employed only 16 people in the U.S. and 30 in China.
The original ZhuZhu Pets are nine different characters, with names including Chunk, PipSqueak, Mr. Squiggles, and Num Nums. There are various accessories for creating customized hamster habitats. ZhuZhu Pets can be put in either of two play modes: "nurturing mode," in which they coo and purr, or "adventure mode," in which they explore their habitat and respond to various stimuli.
ZhuZhu Pets were a craze during the 2009 holidays. They originally retailed for $9 USD, but for a time they sold for over $60 because of shortages.
In December 2009, testing done by the consumer organisation GoodGuide was initially thought to have found more than the allowed level of the toxic, silvery metalloid antimony in the Mr. Squiggles toy. After a review, regulators from the U.S. Consumer Product Safety Commission said that the toy was within the "very protective" standard. GoodGuide subsequently issued an apology saying that their testing methods (which checked for surface toxins) were different from the federal standards (which check for soluble toxins.)
Cepia encourages collecting of ZhuZhu Pets. Exclusive pets have been released in collaboration with Hallmark, Build-A-Bear Workshop, and Toys "R" Us. In early 2010 a set of new characters was released, including the Rockstar pets (Roxie, Ryder, Pax, and Kingston), inspired by the children of celebrities such as Angelina Jolie and Gwen Stefani.
In mid-2010 the Kung Zhu line of battling hamsters was released, aimed at boys age 8–12. They feature a storyline with a Special Forces army battling Ninja Warriors. In December 2010 the ZhuZhu Princess series was released. Also released in 2010 were the first edition of ZhuZhu Babies, which are not electronic or plush, but plastic toys articulated with a small ball under their tummy. The second 2011 edition of ZhuZhu Babies included motors. Also in 2011, several dog breeds of ZhuZhu Puppies were introduced. They are plush robotic puppies that move around and bark.
A new animated series The ZhuZhus will air on September 12, 2016 on the Disney Channel in the United States and in 2017 on YTV in Canada.