Niall Horan went on one of the “craziest” rides that a kid could ever go on.

At 16, he auditioned for “The X Factor” with no formal training, put through to the next round and met his future One Direction bandmates — Louis Tomlinson, Liam Payne, Zayn Malik and Harry Styles.

Together, the group filled stadiums and sold more than 70 million albums worldwide before they disbanded in 2015. But after finding so much success, Horan tells TODAY’s Willie Geist that it almost feels like a dream.

“I’m, like, a bit older,” he told Geist on the June 25 episode of Sunday Sitdown. “…I’m so mature now.”

Horan said he started reflecting on the last 10 years of his life during the height of the COVID-19 pandemic. That’s when he realized that his time in One Direction almost feels like a different reality compared to the present.

“It nearly feels like it’s a separate life now,” he told Geist.

“I definitely have a wiser, like, a good outlook on things, looking back. I didn’t lose the plot along the way,” he added, with a laugh.

When Horan was initially thrust into fame he remembered thinking that he had just been through “the craziest thing that could possibly happen to someone.”

The band’s first hit single, “What Makes You Beautiful,” was taking over the charts and they were starting to be well-known all over Europe and the U.S.

“It snowballed very fast,” he said. “And the rest is history, I suppose.”

At the beginning of their success, they were “in a state of shock the whole time,” he said.

“I think that was what attracted a lot of people to the band. I think it was very clear that it was five working-class, blue-collar kids who were just the deer in the headlights and are now, like, these worldwide-known people,” Horan said. “We always used to say, like, ‘Normal people doing an abnormal job,’ which is a good outlook to have.”

Occasionally, Horan said that he and his bandmates would just look at each other and go, “This is nuts.”

But when Horan, Tomlinson, Payne, Malik and Styles all went their separate ways in 2015, they had to decide what to do next. While they are often asked about the possibility of reuniting down the line — with Styles most recently telling James Corden he’d “never say never to that” — the former bandmates have moved on.

In 2017, Horan released his debut studio album, “Flicker,” which conquered the American albums charts, according to Forbes. Then, in 2020, he released his second studio album, “Heartbreak Weather,” which came out at the same time he was making songs for his third album, “The Show.”

“‘The Show’ is basically me saying how grateful I should feel for everything, because, during the pandemic, we kind of lost all of that control that we like to have as humans,” Horan told Geist.

In early 2023, Horan also joined “The Voice” as one of its coaches and won the entire singing competition with contestant Gina Miles, who was part of his team.

“I was like, ‘Do I want to go back into something like that? I’ve never mentored anyone before,'” he said. “But it was the best decision I made. It’s so much fun.”

Now, with three albums under his belt, Horan says he has no intention of slowing down.

“There’s always a level of trying to prove yourself,” he said. “Hopefully, you write a good song here and there, and there’s a bit of longevity to it. I’ve been doing it for, what is it, f—ing 14 years now? I really hope it doesn’t stop anytime soon.”