Are Your Ankle Socks Aging You? Crew Socks Become a Gen Z Marker.

Like many members of Gen Z, Kalissa Persaud is not about to be spotted in a pair of too-short socks. Ms. Persaud, 22, who lives in Queens, almost exclusively wears crew socks that reach her calves: “I’ve gotten so used to not seeing my ankles that it would be really jarring if I did.”

Night Noroña, 18, who lives in San Diego, recently threw away all of his socks that hit below the ankle. He said he knew hardly anyone who wore them, except for his father. “I’m like, ‘You’ve got to get some longer socks on you,’” he said.

Gen Z has already taken on shibboleths of millennial fashion like skinny jeans and side parts. Now some young people are declaring a preference for crew socks, which generally rise to midway up the shin, and thumbing their noses at the ankle and no-show varieties that are staples of the previous generation’s sock drawers.

What might be just a mild generational difference in sock preferences is being exaggerated into a kind of theatrical warfare on social media. Jabs are being exchanged. Side-by-side comparisons are being posted. And some millennials are standing their ground.

“You will pry these ankle socks off my cold, dead feet,” the comedian Matt Bellassai says in one of the many TikTok videos posted by millennials in recent months, defending their bare ankles.

The conversation has been circulating since at least October, when the podcaster Phoebe Parsons argued in a widely viewed TikTok video that ankle-height socks were a telltale sign of age. (“I’m a millennial,” she says in the video, holding up her foot, clad in a no-show sock.)

The sock divide seems to have become more pronounced ever since. The singer Billie Eilish, 22, wore red crew socks to the 2024 Golden Globes, and the basketball star Angel Reese, also 22, wore tall socks with both sneakers and heels in a photo shoot for Teen Vogue. “Jennifer Lawrence Bravely Steps Out in Millennial Socks,” read a headline in British Vogue this week.

Everyday Gen Z-ers are wearing Nike Dri-FIT crew socks to school with Converse high-tops and mini Uggs. “I think part of growing up is people trying to separate themselves from what came before them,” Mr. Noroña said.

Gen Z’s supposed style rebellion looks an awful lot like the socks that were uncool when millennials were young, said Matt Bunting, 38, who is in the U.S. Navy and lives in Oahu, Hawaii. “It’s just so funny to see the kids nowadays think they’re doing something trendy when all of us laughed at that,” he said.

As a teenager, Mr. Bunting rolled his high socks up under his feet to conceal them beneath low-top skateboarding shoes. It was not very comfortable, he admitted.

“We always want to try to be cooler than our parents or grandparents, so we’ll come up with these ideas,” he said. Usually, “it ends up just being a recycled version of something that already happened.”

Sock trends have typically had a lot to do with youth culture. Bobby socks — white, lacy socks folded over at the ankle — took off among young women in the 1940s. In the 1970s, tall, ringed tube socks exploded alongside the rise of organized sports in the United States.

By the 2000s, offices dress codes were relaxing, and customers were seeking a lower, more casual alternative to dress socks, said Randy Goldberg, a founder and the chief brand officer of Bombas. The company was started in 2013 with ankle socks as its top sellers.

But its sales of taller sock styles have ticked upward in the past two years, Mr. Goldberg said. In response, Bombas introduced a “half calf” crew sock in January that now makes up 5 percent of the company’s total business — although Mr. Goldberg said he still hoped to appeal to customers “whether you’re on one side of the sock war or the other.”

Young people say they gravitate toward Nike crew socks in neutral colors or similar pairs from Aritzia and Uniqlo. Other companies are eager to insert themselves into the conversation: “Crew Socks Are In,” reads a sponsored post for the activewear company Lululemon.

At least some millennials are crew-sock-curious. Renee Reina Grenon, a 39-year-old podcast host in Ontario, Canada, ordered a six-pack of crew socks on Amazon after seeing that they were popular among Gen Z. She said she has been urging her husband to lose the ankle socks, too.

“I’m trying to explain to him that it’s not cool anymore,” she said.

Shae Punzal, a 17-year-old in Carmel, Ind., chalks up the sock frenzy in part to a tendency to play up intergenerational differences online. She thinks millennials should worry less about wearing “trending socks” and wear whatever makes them feel comfortable.

Shae’s mother recently plucked a pair of crew socks from her daughter’s laundry and put them on over her leggings. “Do I look young now?” she asked.