On Facebook, we try to show people the ads that are most pertinent to them. That’s why we’ve always used relevance as a factor in determining how we deliver ads. Taking relevance into account helps ensure that people see ads that matter to them, leading to a better experience for people and businesses alike.

Beginning this week, we’re going to start showing relevance scores as a visible metric in our ads reporting tools. Here’s what advertisers should know.

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. The score is updated as people interact and provide feedback on the ad. Ads with guaranteed delivery — like those bought through reach and frequency — are not impacted by relevance score. Relevance score has a smaller impact on cost and delivery in brand awareness campaigns, since those ads are optimized for reaching people, rather than driving a specific action like installs.

Understanding relevance scores helps advertisers in a few key ways:

It can lower the cost of reaching people. Put simply, the higher an ad’s relevance score is, the less it will cost to be delivered. This is because our ad delivery system is designed to show the right content to the right people, and a high relevance score is seen by the system as a positive signal.

Of course, relevance isn’t the only factor our ad delivery system considers. Bid matters too. For instance, if two ads are aimed at the same audience, there’s no guarantee that the ad with an excellent relevance score and low bid will beat the ad with a good relevance score and high bid. But, overall, having strong relevance scores will help advertisers see more efficient delivery through our system.

It can help advertisers test ad creative options before running a campaign. Advertisers can test different combinations of image and copy with different audiences, and learn which combinations offer the highest relevance scores.

It can help optimize campaigns already in progress. While ad campaigns are running, advertisers can monitor their relevance scores. If a score begins to dip, it may be an indicator that the ad’s creative or audience needs to be refreshed.

While understanding relevance scores has real benefits for advertisers, it’s important to keep this metric in perspective. Relevance scores should not be used as the primary indicator of an ad’s performance. As has long been the case on Facebook, the most important factor for success is bidding based on the business goal you hope to meet with an ad.

Say, for instance, you own a pizza shop and want to run a campaign that drives people to order through your website. Achieving the desired outcome — in this case, driving sales online — is ultimately more important than your relevance score. If you have an average score but your ad is working, you may not want to change anything. Or you may consider tweaking the ad to see how you can get lower cost of delivery by improving the relevance score. Or you might monitor your relevance score, along with the sales you’re driving, to learn when it’s time to update your campaign.

Use relevance scores as a way to reach your audiences at lower cost, and to test and learn about your ad creative and ad targeting. But understand that having a good relevance score is not an end unto itself.

Relevance score rolls out globally starting this week; it can be viewed in any of our ads reporting tools and is also available through our ads API to our partners and ads API developers. To check your ads’ scores, head to Ads Manager and add the relevance score tab to your ads report(s).