We know him as Jack Black, Po, Bowser, and Dewey Finn. But, the 56-year-old comedian "was not always Jack."
Jack, who stars in The Super Mario Galaxy Movie, was born Thomas Jacob Black on August 28, 1969. So where did Jack come from? During a 2009 interview on The Howard Stern Show, the actor opened up about how he earned his rhyming name.
"I was always Black but I was not always Jack," he explained. "My legal name is Thomas Jacob Black. Jack was my nickname, my dad and mom called me Jack."
© Ron Galella Collection via Getty ImagesThe School of Rock actor continued: "There was history behind it. My dad's dad was Thomas and his [dad's name was Thomas]. And it goes back to, like, the ancient Ireland blacksmiths. There was a Thomas Black."
"They knew I was Jack, and I resented it, and so I was like, I just am Jack," he added.
Jack carrying on the legacy
Jack met his future wife, Tanya Haden, in high school, but they didn't start dating until 2005. "I didn't date Tanya or talk to her or anything in high school," Jack recalled to Parade in 2015. "I was pretty shy. I just watched her from afar. We only started dating 20 years after high school."
The same year Jack and Tanya eloped, they welcomed their first son, Samuel, 19. Two years later, Tanya gave birth to their second son, aptly named Thomas, 17, after the Black's family name.
© GettyDuring his 2009 appearance on The Howard Stern Show, Jack explained the decision to name his youngest Thomas.
"I felt the pressure and I named my son Thomas," the actor noted. "When push came to shove I couldn't break the chain. I call him Tommy. Tommy's also my favorite album. The Who's Tommy."
It seems that Tommy is a lot like his dad. Inspired by Jack's role in Kung Fu Panda, Tommy apparently loves martial arts. In 2015, Jack shared on The Tonight Show with Jimmy Fallon: "He literally jumps out and surprises me. I have to be on guard at all time."
© GettyOther celebrities who changed their names
It's not unusual in Hollywood for actors to change their names. Brad Pitt was born William Bradley Pitt. And Emma Stone, whose real name is Emily, has gone by a few different names as an actor.
"I actually adopted a stage name for, I would say, like six months," the actress told Stephen Colbert in October 2025. "Because the Screen Actors Guild, it's like the Business Bureau. You can only have one person with that name."
© WireImageShe went on: "I was 16, and I decided I wanted to be Riley for like six months. So I was Riley Stone, which is a beautiful name. But I did an episode, like a guest part, on Malcolm in the Middle, and they kept going like, 'Riley! Riley!' And I had no idea who they were talking to."
"Truly. And I was like, 'I cannot be Riley.' Like, it's such a... It came out of nowhere. I was just like, 'Cool name. I'll just be RIley.' So I then changed it to Emma because it's close enough to Emily," she added.
