Online shoppers in the US have spent 24 per cent more so far this holiday season than last year, comScore Networks claims.

Non-travel online consumer spending reached $9.75 billion between November 1 and December 2, as online shoppers bought a wider variety of products and also showed willingness to spend on pricier items than during the same period last year, according to the market research firm.

Some categories are outpacing the overall market, such as sport and fitness, where spending is up 59 per cent; furniture, appliances and equipment (up 50 per cent); and apparel and accessories (up 37 per cent), according to comScore. Overall, spending growth should remain steady at 24 per cent through the end of December, the firm said.

Reporting results from a study conducted between June and August, NetRatings Inc.'s Nielsen/NetRatings said on Friday that 18 per cent of online shoppers generate 46 per cent of total spending. Consequently, online retailers need to identify these buyers, which Nielsen/NetRatings calls "most valuable purchasers" or MVPs, and come up with ways to attract, retain and reward them.

The typical MVP uses comparison shopping websites heavily, tends to have a higher income than less-active buyers and has a broadband connection to the Internet, the market research firm said.