Note: Metrics shown in this section are derived from post level lifetime values for content posted within the selected period. 

Reach: The number of unique people who saw any content associated with your page. 

Engagement: The number of times people engaged with your page by clicking on any of the content without generating a story. 

Organic Reach: The total number of unique people who visited your page, or saw your page or one of its posts in the newsfeed or ticker excluding sponsored stories or Ads. These impressions can be fans or non-fans. 

Paid Reach: The total number of unique people who saw a sponsored story or Ad about your Page. These impressions can be fans or non-fans. 

Photo Views: The number of times people clicked or viewed your photos. 

Link Clicks: The number of times people clicked on links posted on your page. 

Video Plays: The number of times people clicked or played your videos. 

Other Clicks: The number of times people clicked on any content associated with your page, excluding photo clicks, video click, and link clicks. E.g. clicks on user’s names in the comments, clicks on the Reactions count, and clicks on the time etc.

Post ER: Average engagement rate per post.

Daily Post ER: sum of single day ERs / number of days in time period

Post Er By Reach: Average engagement rate per post. It includes likes, comments, shares, clicks and reactions.

For more information on Facebook metrics, please refer to the following FB developer resource: https://developers.facebook.com/docs/graph-api/reference/v20.0/insights