More than a quarter (27 percent) of Brits have no idea if someone has posted something about them online, says Symantec.
Research by the security firm also revealed that 40 percent of consumers don't actively protect their reputation or manage the information that's posted on the web about them. Of these, 59 percent believed it was never an issue, while 20 percent said they had no idea where to start.
Half of all UK adults post content about themselves online. Nearly two in five (38 percent) said they post comments on social networking sites, while 29 percent post photographs.
Furthermore, nearly a quarter said they'd posted something they wouldn't want a future employer or teacher seeing, with photographs being the most popular content, named by 14 percent.
Over a third (35 percent) said they could not work in politics based on the information about them available online and more than half (51 percent) said if a 'reset' button that allowed them to remove all content online and start again existed, they'd use it.
"The Digital Age is transforming our society by bringing us closer together. These survey findings show that, as with any major societal shift, we are in the process of adapting," said Janice Chaffin from Symantec.
"The key will be to define the boundaries that work best for each of us so that we can enjoy the incredible benefits of being so connected while also protecting our futures."
Symantec advised web users concerned about their 'digital tattoo' to conduct a comprehensive search using all the names they've used on public records and online, as well as using image and blog functions on search engines to uncover photos or commentary that may have been posted about you.
Furthermore, Brits should never post photos or information that they wouldn't want to be seen by a prospective school, employer, or even a blogger/journalist and they shouldn't rely on default privacy settings. Those that have a common name should consider a middle initial when posting online to avoid being mistaken for someone else.
The security firm also said web users should periodically scrutinize and evaluate their online identity.