People rely on the internet for easy access to information, setting up potential confusion about the boundaries between an individual's knowledge and the information they find online. Across four experiments, we replicated and extended past work showing that online searching inflates people's confidence in their knowledge. Participants who searched the internet for explanations rated their explanatory ability higher than participants who read but did not search for the same explanations. Two experiments showed that extraneous web page content (pictures) does not drive this effect. The last experiment modeled how search engines yield results; participants saw (but did not search for) a list of hits, which included "snippets" that previewed web page content, before reading the explanations. Participants in this condition were as confident as participants who searched online. Previewing hits primes to-be-read content, in a modern-day equivalent of Titchener's famous example of a brief glance eliciting false feelings of familiarity.