They’re the greatest generation — of couch potatoes.

A growing number of 18- to-34-year-olds, the world’s largest age group, prefer to unwind by staying in, watching Netflix and ordering Seamless, rather than by getting down at a club or bellying up to a bar.

“The weekend is my time to relax and not do all that stuff,” says Brandon Gillespie, 32, who works in media production. “Once I’m home, I don’t want to go out.”

He’s not alone. More young people are choosing to spend a quiet evening at home.

A study by Taylor Nelson Sofres, a consumer research agency, found that, on average, millennials stream 2.7 hours of TV shows a day, while the earlier generation, Gen X, does about 1.8 hours.

Millennials, it seems, have discovered that the need to socialize face-to-face is waning, as food, shopping, friends, entertainment and even sex are all an app tap away.

The study also found that millennials spend about 3.1 hours a day on their mobile devices, compared with Generation X’s 1.7 hours.

Gillespie, a Harlem resident, watches Netflix and YouTube clips on his phone or computer in his one-bedroom apartment.

As for the challenges of dating, the bachelor says society is moving away from the traditional, “meet cute” mold.

“You know, the whole ‘Netflix and chill,’ whatever you think about it . . . it’s kind of a trend,” he says.

For some, the price of nightlife isn’t worth the payoff.

“It’s cheaper to just stay home,” says Kimberly Pena, 21, a junior at Montclair State University in New Jersey. “Nowadays, $20 won’t get you too far.”

One thing millennials are not bingeing on is booze.

A 2016 survey by Heineken found that when millennials do bother to venture outside, 75 percent drink in moderation.

A study by Child Trends Data Bank also found that binge drinking among teens is at an all-time low: Only 19 percent of high school seniors admitted to binge drinking in 2014, compared with a record high 41.4 percent in 1980.

But experts say staying indoors can hurt a person’s emotional well-being.

“They’re not consuming alcohol, but they’re consuming a lot of media — and it’s depressing them,” says Manhattan clinical psychologist Dr. Michael Brustein.

“I can’t tell you how often I hear [patients] say, ‘I did nothing this weekend and I feel terrible.’ ”

Some might be chained to their beds because of a penchant for sleepiness, too.

Dr. Sanjeev Kothare, a neurologist at NYU Langone Medical Center, says the increase in cases of exhaustion among young people could be as high as 50 percent.

Brooklyn theater artist Misha Lambert, 22, finds her work very exhausting.

“[It] requires me to really go out and to be really social, which is very tiring for me,” she says. “I just want to turn off that part of me and I just want to sit around and be comfortable.”

Gillespie admits that while many of his friends are “homebodies,” some do worry about his hermit-like tendencies.

“I have to convince people that it’s OK,” he says.

“I enjoy not having to interact with people.”

College kids are way too sensitive: