Antivirus expert McAfee has announced the launch of its new Privacy service, which will allow parents to restrict their children's use of the internet.

This is the first time McAfee has offered such a filter system and, to show potential customers what it can provide, it is offering a 30-day free trial. The service will cost £21.95 per year.

There are plenty of free filters on the market, but McAfee says its US sales have already shown people are willing to pay for such a service.

"We have proven there is a market for Privacy services," said Shawn Woolfe, director of marketing communications at "[In the US] we sell hundreds of subscriptions every day."

Internet watchdog the Icra (Internet Content Rating Association) launched its filter system back in March.

It's free-of-charge service has two layers. The first requires websites to grade themselves based on how suitable their content is for different age groups. To date, some of the world's most visited sites, including AOL, MSN and Yahoo, have successfully labelled around 93 percent of their sites. The second layer allows parents to design their own templates.

But McAfee says its filter software is far more complex than Icra's, offering age-based access levels for every member of the family and managing cookies and web-advertising activity.

"Our features and functions [are] far beyond those offered by the free services today. It also acts as an identity protection tool to ensure that your personal information does not leave your computer," said McAfee's Woolfe.

The software also provides a number of security services such as blocking transmission of phone numbers and credit card services.

But whatever method of filtering parents choose, it is essential that they are at least using something.

"What is crucial is that children aren't getting access to things they shouldn't be. We as parents simply can't be there to watch them all the time," said a spokesman at Icra.