Bieber was playing a game of "Burning Questions" with host Ellen DeGeneres when he was asked to name the "best gift" he got for his birthday.
"My wife did up my house really nicely, and she had a movie playing. It was this really romantic night," he said.
Bieber said Baldwin worked with a wedding planner to bring her "gorgeous" vision to life.
"She basically got a serious wedding planner-type style thing, and did it all in candles," he said.
During the game, Bieber also shared how Baldwin's pet name for him is "goo-goo."
"[It's] kind of weird, but I like it," he said. "She's got me wrapped around her finger, pretty much."
When asked how many kids he wants to have, Bieber said it's up to Baldwin.
"I think it's up to Hailey, because it's her body," he responded.
Baldwin marked Bieber's birthday in an Instagram post Sunday, calling the "Yummy" singer her "best friend."
"happy birthday best friend," she wrote. "thank you for putting a smile on my face every single day.. I love you."
Bieber and Baldwin married in September 2018, and had a second wedding ceremony with family and friends in October. Bieber said in an interview with Apple Music in February that his marriage to Baldwin influenced his new album, Changes.