Joel Thomas Zimmerman (born January 5, 1981), better known by his stage name deadmau5 (pronounced "dead mouse"), is a Canadian progressive-house music producer and performer from Toronto, Ontario.

Zimmerman produces a variety of styles within the house genre and sometimes other forms of electronic music. His tracks have been included in numerous compilation albums such as the 2007 In Search of Sunrise 6: Ibiza CD. The February 2008 issue of Mixmag 's music magazine included a free CD which was titled MixMag Presents: The Hottest New Name In Dance! DEADMAU5 Tech-Trance-Electro-Madness, mixed by Zimmerman. Tracks have also been included and presented on Armin van Buuren's A State of Trance radio show. His debut album, Get Scraped, was released in 2005, followed by others in the next few years. Today, deadmau5 is one of the highest paid electronic artists in the world. He has received six Grammy nominations for his work.

As well as his own solo releases, Zimmerman has worked alongside other DJs and producers, such as Kaskade, MC Flipside, Rob Swire of Knife Party and Pendulum, Wolfgang Gartner, Bighorse, and on a number of releases, he has partnered with Melleefresh. An early 12" single produced on vinyl titled "I Don't Want No Other" was released by Joel Zimmerman under the alias "Dred and Karma". The 2006 album titled deadmau5 Circa 1998–2002 was released using the alias "Halcyon441". He has also collaborated with Steve Duda under the alias, "BSOD", as well as "WTF?" including Duda, Tommy Lee, and DJ Aero.