Search engine Ask has come up with a new weapon in its battle to win more users: privacy.

The search website, which is owned by media mogul Barry Diller's InterActive Corp, today announced the launch of a new online tool that helps surfers keep their internet search history private. The system, called AskEraser, allows users delete any record of the searches they have made using the Ask site – including removing the information from the company's servers.

The company's rivals - such as Google and Yahoo - currently retain information on searches for as long as 18 months, but then anonymise that data or delete it entirely. Ask, however, says it will take user considerations into account by allowing them to turn on extra privacy settings and delete such information immediately.

"For people who worry about their online privacy, AskEraser now gives them control of their search information," said Jim Lanzone, the chief executive of Ask. "We take significant steps to protect any data that's stored in our servers, but for those people who want to take extra precautions AskEraser lets them take the issue completely off the table."

"Race to the bottom"

Questions have been raised recently over the amount of information held by internet companies, with particular concerns over the influence of Google and social networking sites like Facebook. Earlier this year Google was accused by lobby group Privacy International of leading a "race to the bottom" because of the vast amount of information it stores on users.

The criticisms came despite the company's successful fight to protect user data after an approach by the US government to gain access to its databases.

Although Google recently changed its policies so that it retained anonymised search information, its proposed $3bn takeover of advertising company DoubleClick has seen more criticism. The European Commission announced last month that it was to mount a detailed investigation into possible competition concerns over the deal.

Ask will be hoping that its new tactic – which was heralded by an anti-Google advertising campaign earlier this year – pays off. According to recent figures, Ask is used for just 1% of all internet searches around the world. But privacy is becoming an increasingly important issue, say experts – thanks in particular to a series of British government data scandals.

"The computers that underpin online services have vastly superior recall," said David Tansley, technology partner at Deloitte. "Many internet users are probably aware that cookies keep a log of every site visited, but few surfers may be aware that until recently companies could hold on to such consumer data for decades."