Twenty-somethings Andrew Dost, left, Nate Ruess, center, and Jack Antonoff all had years of experience playing in bands before teaming up as indie-pop group Fun.

The three members of the New York City-based buzz band Fun. are only in their mid-20s, but they’re already rock ’n’ roll veterans.

“My first tour was when I was 15, in my parents’ minivan,” recalls guitarist Jack Antonoff, formerly of the short-lived, New Jersey-based group Steel Train. Drummer Andrew Dost was in the Chicago band Anathallo, and vocalist Nate Ruess was a member of Arizona band the Format. “[Ruess and I] were both signed to major labels when we were 17,” says Antonoff.

So, it’s ironic that Fun. would break out with a radio anthem called “We Are Young.” “Let’s set the world on fire,” goes the rousing, sing-along chorus. “We could burn brighter than the sun.”

Antonoff says the success Fun. now enjoys (sophomore disc “Some Nights” debuted at No. 3 on the Billboard 200 chart in February) is a result of those early efforts, which may not have produced memorable music but taught them all how to be in a band. “We screwed up so many things and had so many horrible experiences, but by the time we came together as Fun., we knew how to make it work,” he says.

Featuring backing vocals by oddball R&B heroine Janelle Monáe, “We Are Young” draws from older influences that include Harry Nilsson, Queen, Fleetwood Mac and even Bruce Springsteen. The massive hit has already inspired YouTube parodies, including “We Are Drunk” and the rather depressing “We Are Not Young.”

The band welcomes such reinterpretations. “My first thought was, ‘We’re culturally relevant enough to have a parody,’” says Antonoff. “I love when songs and artists can be something that everybody knows and talks about.”

That is the core mission of Fun.: to provide a communal experience for its listeners, to soundtrack its generation, to be a touchstone that unites millions.

“We’re not making songs that we want six people in America to listen to on a 7-inch single,” says Antonoff. “We’re making music — in a completely unashamed way — that we want to play in an arena, and we want a billion people to hear it. And, most of all, we want it to affect people in the same way that we’ve been affected by music.”

Track to Try: If Fun. intends to be the biggest band in your life, its smash hit “We Are Young” is the perfect vehicle, with a chorus that’s both vertiginous and catchy, and lyrics that describe nights on the town in almost anthropological detail. And yes, that period after the band’s name IS intentional.

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