title: Facebook long-lived and short-lived access tokens, and their expirancy after offline_access removal
body: <p>While reading Facebook's post regarding <a href="https://developers.facebook.com/roadmap/offline-access-removal/" rel="noreferrer">offline_access permission removal</a>, I was thoroughly confused by their reference to short-lived and long-lived access tokens.</p>
  
  <p><a href="http://developers.facebook.com/docs/authentication/" rel="noreferrer">This page</a> mentioned </p>
  
  <blockquote>
    <p>The duration for which a given access token is valid depends on how it
    was generated</p>
  </blockquote>
  
  <p>But I failed to find any further information.</p>
  
  <p>Anyone has insights on how this determination process works in detail?</p>