Webroot, developer of the Spy Sweeper antispyware software, has launched a new parental control tool.

Child Safe lets parents manage when their children surf the web, what types of sites they visit, what applications they can open and for how long. Webroot also emails parents easy-to-read reports of sites their kids visit.

Along with using traditional blacklists for blocking sites, Child Safe's dynamic web analysis can block all or part of an unknown site. Webroot says Child Safe operates on the network layer of the OS and does not slow down web surfing as much as parental controls programs that hook into the higher-level application layer might.

When evaluating whether images contain questionable content, such as nudity, Webroot analyses metadata rather than the image itself.

The tool has been launched in the US initially, for $40 (about £21).