Beginning this week, we’re going to start showing relevance scores as a visible metric in our ads reporting tools.Facebook Advertisers To Get Ad Relevance Scores [facebook.com]

Relevance score is calculated based on the positive and negative feedback we expect an ad to receive from its target audience. The more positive interactions we expect an ad to receive, the higher the ad’s relevance score will be. (Positive indicators vary depending on the ad’s objective, but may include video views, conversions, etc.) The more times we expect people to hide or report an ad, the lower its score will be.
Ads receive a relevance score between 1 and 10, with 10 being the highest.

Relevance score rolls out globally starting this week; it can be viewed in any of our ads reporting tools and through tools developed by our API partners.