Online ad spend in the US is set to hit $9.4 billion (€7.1bn, £4.9bn) by the end of this year.

The figure represents a rise of 30% over the last year, four times the annual growth of the overall American advertising industry. Researcher eMarketer is forecasting web ads will make up 4% of the total market next year and the spend will rise to $11.3bn.

The huge growth in web advertising has its roots in increasing use of visual ads that splash across web sites; quicker internet connections; accurate tracking technology; and advertisers' growing confidence in the medium.

Says Dan Ciporin, ceo of, a comparison-shopping site: "The internet has been incorporated into the media mix, along with TV, newspapers and magazines. Increasingly, it's part of every company's media buy."

A survey by the American Advertising Federation reports advertisers are planning to increase their online spend to 17% of the their total budgets by 2007.

The largest US internet portals are now charging up to £300,000 per 24 hours for advertising, and even though online ads are unlikely to overtake TV or newspapers, says analyst Nate Elliott of JupiterResearch: "It's making offline advertising grow a little more slowly than it otherwise might."

Data sourced from USA Today Online; additional content by WARC staff