Website recommendation service StumbleUpon has boosted its revenue earning potential by expanding advertising services.
Dubbed StumbleUpon Paid Discovery, the service offers analytics and other features at an additional cost to advertisers.
Paid Discovery is priced at 10 cents and 25 cents a visitor, compared with 5 cents for the standard advertising option.
For the extra money, advertisers get priority ad serving, the ability to display ads on mobile devices, and more detailed analytics, including sharing behaviour across social media sites like Facebook and Twitter.
The launch of Paid Discovery comes just a week after StumbleUpon announced new funding of $17m, according to US reports.
StumbleUpon executives said Paid Discovery was more effective than banner or search ads because it placed entire webpages and videos into selected user streams.
As with the existing service, Paid Discovery customers will be able to target their content at users on the basis of age, gender, location and over 500 topics of interest.
Ratings of the sponsored sites are then used to determine how often and in which users' content streams they appear.
Paid Discovery is part of StumbleUpon's plans to expand the business, which has grown by more than 14m registered users since it split from eBay in 2009.