Relevance ranking: How Search.gov ranks search results

Use this information on relevance ranking to ensure that the best, most appropriate content rises to the top of search results to help the public find what they need.

Promoting results

For any page you want to appear as the first-listed search result, use a Best Bet.

Best Bets allow you to “pin” recommended pages to the top of the search results. Read our tips on how to set up Best Bets to learn more.

Ranking factors

Each of the following ranking factors is calculated separately, and then multiplied together to create the final ranking score of a given item for a given search.

File type

We prefer HTML documents over other file types. Non-HTML results are demoted to prevent, for example, PDF files from crowding out their respective landing pages.

Freshness

We prefer documents that are fresh. Anything published or updated in the past 30 days is considered fresh.

After that, we use a decay function to demote documents, so that the older a document is, the more it is demoted. When documents are 5 years old or older, we consider them to be equally old and do not demote further.

We use either the article:modified_time on an individual page, or that page’s <lastmod> date from the XML sitemap, whichever is more recent. If there is only an article:published_time for a given page, we use that date.

Documents with no date metadata at all are considered fresh and are not demoted. Read more about the date metadata we collect and why it’s important to add metadata to your files.

Page popularity

We prefer documents that users interact with more. We use data from the Digital Analytics Program and our own search analytics to track the number of times a URL is clicked on from the results page.

The more clicks, the more that URL is promoted, or boosted. We use a logarithmic function to determine how much to boost the relevance score for each URL.

Note that sites using the search results API cannot take advantage of this click data.