“They’re like Ralph Nader without the politics,” said Victor Navasky, former publisher and editor of The Nation. “So it’s amusing that what they do comes across in conventional, capitalist terms  helping people who want to spend their money to spend it and get value for it, and pushing corporations to perform better.”

Mr. Guest sees no incongruity in any of this. “We have to think and act like a business,” he said, seeing readers as the shareholders.

That meant, among other things, more aggressive placement of the magazine in checkout aisles and newsstands, and buying a long list of sponsored search terms on Google and Yahoo. Fierce competition for terms like “S.U.V.” puts those words out of Consumer Reports’ price range, but there is substantially less clamor for the rights to, say, “toaster.”

Subscriptions to the magazine still produce the vast majority of Consumers Union’s revenue: the dead-tree version of Consumer Reports has a paid circulation of 4.5 million, more than all but a handful of American magazines. There is relatively little overlap between the print and Web subscribers  about 600,000  which allows the magazine to reach two large, distinct audiences.

More than 60 percent of the print magazine’s readers are men, but the Web site, where readers are split almost evenly by sex, has helped Consumer Reports draw more women. Online readers average 50 years old, a decade younger than print readers, and are better off financially.

A reader of the printed magazine might be “someone who generally wants to be a well-informed consumer,” said Giselle Benatar, editor in chief of online media. “But on the Web site, we’re attracting very transaction-minded consumers. They are shoppers. They’re looking for a product, they want ratings, they want recommendations, and they want it now, not once a month.”

Image The resolution of a camera lens was tested at the groups office. Credit... Joyce Dopkeen/The New York Times

The site has been steadily built up, with additions like, this year, crash test videos  front and side impact  on nearly every vehicle sold in the United States. One of the site’s primary attractions is its deep well of product ratings  not only more data on some products than will fit in the magazine, but also ratings published months or years ago. It can also produce reviews of new products like the iPhone much faster than the magazine, as well as safety warnings on things like lead paint in toys, which are always available on the free portion of the site.