Michael Ryan Pritchard, now known as Mike Dirnt, was born on May 4, 1972. Mike's mother was a heroin addict. He was given up for adoption when he was a baby to a Native American mother and a white father. When he was 7, his adoptive parents got a divorce. Mike lived with his father for a while, but confrontations sent him back to his mother. He lived there on the borderline of proverty, while his sister left home at the age of 13. "There were all sorts of things happening," says Mike. "When I was in fourth or fifth grade, my mom stayed out all night, came home the next day with a guy, and he moved in. I'd never met the guy before, and all of a sudden he's my stepdad. We didn't get along for years. Later on, when I hit high school, my mom moved away from us, and me and my stepdad got real close. He instilled a lot in me. The one thing my family did give me is blue-collar morals. But then he died when I was 17."

By that point, Mike had already moved out, leaving home when he was 15 to live out of his truck. He then rented a room in Billie's mom's house, and later he lived in a punk squat. Billie and Mike began living for their weekends at the Gilman Street Project. Mike still continued to go to school, play in Sweet Children (which later became Green Day, of course), and live on his own. He supported himself by working as a cook. Mike almost didn't graduate from high school, because his mother refused to sign one of his mandatory-attendance forms. "I took my mom aside," Mike says. "I said, 'This is how it is. You have so much shit going on in your life, so if once every semester you ask me if I've done my homework and jump all over my case, that's not right. Have I failed yet? No. And I'm going to graduate if you stay off my back. The one time in your life you chose to have morals, and it's going to fuck me up. Don't play mom once a year. It doens't fucking cut it.'" In the end, Mike did graduate from high school, and he even took more than a year's worth of courses at a community college. Then Billie and Mike moved into a squat in Oakland, California (the inspiration for "Welcome to Paradise").

Mike married his long-time girlfriend Anastacia in 1996, and their daughter, Estelle Desiree was born December 1996. Mike and Anastacia divorced but still remain friends. He remarried in 2003 or 2004 to his then-girlfriend Sarah, but divorced the same year. Mike married his wife, Brittney, in March of 2009. He and Brittney welcomed the birth of their son, Brixton Michael, on October 11, 2008. He and his family now reside in Oakland, California. Mike also owns a cafe/resturant named Rudy's Can't Fail Cafe, named after a song by the Clash. The cafe is located in Emeryville, CA.