Dan Cummins was born and grew up in the small town of Riggins, Idaho (pop. 410). He graduated from high school in 1995, and in 1999 he earned a B.A. in psychology from Gonzaga University in Spokane, Washington. He then worked at a local residential treatment center as a child and family counselor for six months, which he described as a horrible experience. Cummins has two children, a son and a daughter with his former wife, whom he divorced in 2009. Cummins shares custody of his children, who split time between Spokane and Coeur d'Alene, where he currently lives.

In 2000, Cummins had his first taste of standup comedy, performing at the open mic of the now-defunct Laugh’s Comedy Cafe inside the Season Ticket bar near the Spokane Arena. In 2001, Cummins entered the Seattle Comedy Competition, finishing as runner-up. There he met David Crowe, with whom he formed a two-man stand-up/sketch/music act, COBDOG, (Crowe On Bass, Dan On Guitar), the highlight of which was having a radio-friendly version of one of their sketches, titled "At The Coffee Shop," making The Bob and Tom Show best-of CD, Bob And Tom Gone Wild. The duo split in 2003.

In 2005, Cummins performed at the New Faces showcase at the Just For Laughs Montreal Comedy Festival, catching the attention of both Comedy Central and The Late Late Show talent booker. In 2006, Cummins performed on Comedy Central’s Live at Gotham, his first performance recorded for television. A month later, he made his network television debut, performing on The Late Late Show with Craig Ferguson. Also, in 2006, he performed at his second major festival, the HBO Las Vegas Comedy Festival. The year 2007 started off with Cummins performing at the Comedy Central South Beach Comedy Festival, and then booking approximately 100 college dates at the NACA Nationals college booking convention in Nashville. Cummins then recorded his first television stand-up special, Comedy Central Presents Dan Cummins, in August at the Hudson Theater in New York. In 2008, Cummins performed at nearly 100 schools and also advanced to the semi-finals of Last Comic Standing, Season 6.

Later in June 2009, Cummins performed at the second-annual Rooftop Comedy Aspen Comedy Festival. He made two additional television appearances in 2009, appearing on an episode of Byron Allen’s Comedy.TV, and on The Tonight Show with Conan O'Brien the day before Thanksgiving. The year 2009 also included the release of Cummins' first nationally distributed CD, Revenge is Near, on June 23 via Warner Brothers Records. It peaked at No. 7 on the Billboard Comedy Charts, and Punchlinemagazine.com put it in their top 10 list for the best comedy CDs of 2009.

In 2010, Cummins appeared in season two of G4’s The International Sexy Ladies Show, and has moved to Santa Monica, California, where he has begun working with Creative Artists Agency. Cummins also continued to trying to get his television projects into development, while still maintaining a busy tour schedule of colleges, clubs, and theaters. Cummins has numerous videos on the web, with clips from both televised and non-televised routines, along with various web series. Since early 2009, filmmaker Mike Newman has been filming an ongoing documentary on Cummins’ journey through stand-up, and a teaser/trailer of this ongoing documentary was included in the bonus section of the Crazy With A Capital F DVD.

On January 5, 2015 it was announced that Cummins would take over permanent co-hosting duties on The Playboy Morning Show.

On September 18th, 2016 Dan released the first episode of his podcast “Timesuck”.