It is impossible for a user to see who has viewed his Facebook profile. Any third party applications or websites claiming to allow users access to this information are incorrect.
While it is likely that Facebook itself keeps track of which users have viewed which profiles, the company does not disclose this information to its users. Applications that claim to let users view this information often gather information about the user for a third party, possibly infecting the user's computer with malware that may spread to Facebook friends of the user. If the user has already installed such an application, he should remove it immediately.