Because of his father's career as an international banker, Callen lived overseas until he was fourteen years old, including in the Philippines, India, Pakistan, Lebanon, Greece and Saudi Arabia.

[5] Callen's characters included Pool Boy from Cabana Chat with Dixie Wetsworth, motivational speaker Al Casdy, and "relationship-challenged" death row inmate Jeremy Anderson.

[17] Callen also performed impressions of Bill Clinton, Robert De Niro, Al Gore, Luke Perry, Steven Seagal, Sammy Hagar, Kevin Bacon, Jim Carrey, Ted Knight and Arnold Schwarzenegger, among others.

Callen has guest starred on television series such as Entourage,[18] NewsRadio,[19] Oz,[20] Frasier, Suddenly Susan, NYPD Blue, Law & Order: Special Victims Unit, CSI, 7th Heaven,[20] Rude Awakening, Less than Perfect, The King of Queens, Sex and the City, Kingdom, Stacked, Las Vegas, Reba, Fat Actress, Californication and How I Met Your Mother.

The podcast formerly focused on the realm of mixed martial arts, but since their departure from Fox Sports, they regularly discuss pop culture and current events as well.

[32] Schaub and Callen regularly appear alongside Joe Rogan during live event broadcasts, such as the UFC and Glory kickboxing, for what is called the Fight Companion.

[33] In September 2023, Schaub and Callen publicly stated that Kast Media and its CEO Colin Thomson owed their production company $1.5-1.6 million dollars.

Similar claims were made by Jim Cornette followed by Theo Von, Jason Ellis, Whitney Cummings, and Alyx Weiss, who stated they were owed money by Kast Media, including several six-figure and seven-figure shortages.

[34][35][36][37][38] In March 2023, Callen and fellow comedian Nick DiPaolo and Josh Firestine joined Steven Crowder on his network, Mug Club, to stream on Rumble.

In January 2021 Judge Monica Bachner ruled in the couple's favor, stating that Callen "did not meet his burden of demonstrating a probability of prevailing on his claim.