The Adobe Digital Index survey said online sales for the key holiday shopping day reflected an 80 per cent jump in sales from mobile devices like smartphones and tablets. Mobile accounted for some 18.3 per cent of online sales.
Cyber Monday stems from the early days of the Internet, when consumers would use their fast Internet connections at work to make online holiday purchases. But many retailers are extending their deals over several days from the Thanksgiving Day holiday on Thursday.
"Retailers earned 10 per cent of their annual sales in just the last five days, an increase of 26 per cent year-over-year," said Tamara Gaffney, principal analyst for Adobe Digital Index.
Adobe's online shopping data is based on an analysis of nearly 900 million visits to 2,000 retailer websites on Cyber Monday and more than three billion visits since Thanksgiving Day.
A separate analysis by IBM showed Cyber Monday was the biggest online shopping day in history with a 20.6 per cent increase in online sales. IBM said 17 per cent of total online sales came from mobile, an increase of 55.4 per cent year-over-year.
"We continue to see a dramatic movement of the new digitally savvy consumer as Cyber Monday once again proved to be the star of this holiday shopping season," said Jay Henderson of IBM.
"The mobile device has become the shopping companion of choice for consumers, driving record mobile sales."
Forecasters project just three to four percent growth in the entire retail sector this holiday season, while online shopping is expected to soar 13 to 14 per cent in the 2013 season.