NEW YORK » Retailers are rolling out online deals on so-called “Cyber Monday.” But now that shoppers are online all the time anyway, the 10-year-old shopping holiday is losing some of its luster.

Still, today is expected to be the biggest online shopping day ever, with estimates that it will rack up over $3 billion in sales.

“It’s no longer about one day, but a season of digital deals,” said Matthew Shay, president of retail trade group The National Retail Federation.

Online shopping is taking its toll on brick-and-mortar shopping. Frenzied crowds seemed to be a thing of the past on Black Friday — the busy shopping day after Thanksgiving — and sales fell to $10.4 billion this year, down from $11.6 billion in 2014, according to preliminary figures from research firm ShopperTrak.

But as online shopping grows more popular on Thanksgiving and Black Friday, that’s causing less of a frenzy on Cyber Monday, too.

“Consumers are recognizing the Internet is the place to go for a deal any time, any day,” said Gene Alvarez, managing vice president of research firm Gartner.

Retailers have been touting online deals since the beginning of November. And they no longer wait for Monday to roll out Cyber Monday deals, either. Amazon started “Lighting Deals” on Saturday and Wal-Mart beginning all of its Cyber offers on 8 p.m. on Sunday.

Amazon was offering 65 percent off sweaters, Target was touting 15 percent off its whole site for the first time and Wal-Mart offered $500 off a $1200 LG 65-inch 4K Ultra HDTV.

“I personally skip Black Friday just to shop Cyber Monday,” said Mark Flores, a parks and recreation director from Lynwood, California. He was looking online today for tablets for his nephews, nieces and grandparents, leather goods and gift certificates, plus shoes for himself on Amazon, department store sites and the Groupon App. He said he was looking for deals “that are greater than normal sale prices and coupons.”

Research firm Comscore expects online sales to rise 14 percent to $70.06 billion During the November and December shopping period, slowing slightly from last year’s 15 percent rise. Online sales make up 10 percent of overall retail sales, but that increases to 15 percent during the holidays as online shoppers snap up Black Friday and Cyber Monday deals, according to research firm Forrester.

Cyber Monday itself is expected to be the biggest online sales day of the season and ever, surpassing $3 billion in sales. If so, it will be the sixth year in a row that Cyber Monday is the biggest online shopping day ever.

But Thanksgiving and Black Friday are gaining fast. About $4.47 billion were spent online on Thanksgiving Day and Black Friday combined, 18 percent more than last year, according to Adobe, which tracks 200 million visitors to 4,500 retail websites. And 33.2 percent came from mobile devices, up from 27 percent last year.

Amazon is offering new deals every 5 minutes starting Friday, Nov. 20, and extending through Dec. 5 double the cadence of last year. It also is offering more than 150 app-only lightning deals to encourage mobile shopping.

Wal-Mart started offering all of its 2,000 Cyber Monday deals — quadruple the 500 online deals it offered last year — starting 8 p.m. on Sunday the evening before. A year ago, the nation’s largest retailer only offered a sneak peak of about 20 deals on the evening before Cyber Monday.

And Target is offering 15 percent off its entire site on Cyber Monday, its first ever site-wide discount on the shopping day.

Forrester Research analyst Sucharita Mulpuru said even though more people are shopping online and on their phones throughout the season, Cyber Monday will still drive sales from its name alone.

“A lot of people waiting to see if deals are better on Cyber Monday,” she said.

The name “Cyber Monday” was coined in 2005 by the National Retail Federation’s online arm, called Shop.org, to encourage people to shop online. The name was also a nod to online shopping being done at work where faster connections made it easier to browse. Now, even with broadband access, Cyber Monday continues to be a day when retailers pull out big promotions.

“I plan on scoping out the deals,” said Diane Boral, 33, from Oxnard, California, who planned to shop online at Walmart, Target and other stores today. She said she hoped to get most of her Christmas shopping done on Cyber Monday. She was looking for deals ranging from 20 percent to 75 percent off on items like a camera, air conditioner, tires and Christmas gifts.

Most of her shopping is done online via her iPhone and laptop, she said.

“I have more time to browse for items,” online, she said.