What's a "unique visitor?"

Several reports offer Visitors or Unique Viewers tabs, that track and report information on unique visitors accessing your content. You should understand what Akamai considers a "unique visitor," and also recognize why a unique visitor may not be an individual person requesting your content.

  • Unique visitors are the number of unique combinations of client IP addresses plus User Agent (or player ID for streaming). There is no concept of a timeout. IP addresses are tracked per hour, so two hits from the same IP at 1:59:59 and at 2:00:01 would result in separate IP addresses, in separate hours.
  • The number of visitors displayed does not accurately represent the number of actual people accessing your content. Many people can appear as a single IP address by sharing proxies, caches, NAT firewalls or even simply sharing the same computer at home. One person can also appear as many IP addresses by using dynamic IP addressing, being load balanced across proxies and caches, or simply using multiple computers. Other reasons for over-counting include: robots; rogue client software that keeps changing its ID string; users that delete cookies, upgrade software or a user using multiple client software agents. Other reasons for under-counting are clients that don't (or have been set not to) accept cookies or operate through anonymizers. If authenticated logins are used, determining the number of real people from server-side logs may be best derived from a cookie that is only set after an authenticated login, which only holds a value which uniquely corresponds to the user.
  • Visitor data collection is limited to 200 million a day. This exists for efficiency and to optimize data collection. If data volume exceeds the limit, collection is automatically suspended. In the unlikely event of data volume nearing the limit, we proactively work with you to configure your service to avoid automatic suspension.