A report from Goldman Sachs, Nielsen/NetRatings and Harris Interactive found that between Oct. 29 and Dec. 23 retail shoppers in the U.S. spent $30.1 billion online, up 30 percent from the same period a year ago.
Clothing was the top seller in terms of dollar amount, at $5.3 billion total, up 42 percent from last year's revenue, the report said. Computer hardware and peripherals showed the most growth, 126 percent, at $4.8 billion. Consumer electronics was the second fastest growing category, garnering $4.8 billion, up 109 percent.
People spent $3 billion on books online, up 66 percent, and $2.3 billion on products in the toys/video games category of hardware and software, a drop of 9 percent from last year, the study found.
"Computer hardware and consumer electronics had a stellar season with the price reductions for laptops, plasma TVs, (and) color printers as well as high demand for iPods, digital cameras and media accessories," Heather Dougherty, senior retail analyst at Nielsen/NetRatings, said in a statement.
Online sales snared about 27 percent of surveyed consumers' total holiday spending budgets this year, up from 16 percent four years ago, according to the study, which was based on national surveys of more than 8,600 shoppers. The data were weighted to be representative of the total U.S. online population of adults. The survey has a sampling error of plus or minus 3.1 percentage points.
In its own study on the same subject, ComScore Networks found that online retail spending between Nov. 1 and Dec. 25 totaled $18.1 billion, up 25 percent over the $14.5 billion a year earlier. The busiest days were Dec. 12 and 13.
"The growth of 25 percent we're now seeing versus a year ago is slightly ahead of our initial forecast of 24 percent growth, reflecting the aggressive price discounting offered by online merchants late in the season and consumers' increased confidence in expedited shopping," the study said.
ComScore found that computer hardware was the top seller in terms of dollars at $4.1 billion, up 14 percent from a year earlier, followed by clothes and accessories at $3 billion, up 37 percent, and consumer electronics at $1.3 billion, up 20 percent.
Computer software sales rose 35 percent, and video games, consoles and accessories rose 34 percent, benefiting from the release of Microsoft'sthis month and Sony's earlier in the year.
Meanwhile, a KPMG study released on Thursday found that more than half of consumers reported making an Internet purchase during the holiday shopping season.
"Particularly interesting is thatup to 65, with 53 percent of consumers making Internet purchases," John Rittenhouse, national partner in charge of KPMG's operations risk management practice, said in a statement.