About 10 minutes or so of inactivity on Plenty of Fish and you'll automatically get logged out.
POF logs you out as well however, POF's automatic log out seems to be pretty quick. In fact, many websites will log you out after a certain period of time, even if you remain active on the site. All websites you are required to log into, like Plenty Of Fish dating, automatically sign you out of their website after a certain period of inactivity.
