Google uses content previews, including text snippets and other media, to help people decide whether a result is relevant to their query. The type of preview shown depends on many factors, including the type of content a person is looking for and the kind of device they're viewing it on.
For instance, if you look for recipe results on Google, you may see thumbnail images and user ratings--things that may be more helpful than text snippets when it comes to deciding what you want to eat. Alternately, or perhaps you're looking for a concert nearby, and are able to check out the events directly in the search results. These are made possible by publishers marking up their pages with structured data.
Google automatically generates previews in a way intended to help a user understand why the results shown are relevant to their search and why the user would want to visit the linked pages. However, we recognize that site owners may wish to independently adjust the extent of their preview content in search results. To make it easier for individual websites to define how much or which text should be available for snippeting and the extent to which other media should be included in their previews, we're now introducing several new settings for webmasters.
Letting Google know about your snippet and content preview preferences
Previously, it was only possible to allow a textual snippet or to not allow one. We're now introducing a set of methods that allow more fine-grained configuration of the preview content shown for your pages. This is done through two types of new settings: a set of robots meta tags and an HTML attribute.
Using robots meta tags
The robots meta tag is added to an HTML page's , or specified via the x-robots-tag HTTP header. The robots meta tags addressing the preview content for a page are:
"nosnippet" - This is an existing option to specify that you don't want any textual snippet shown for this page.
"max-snippet:[number]" - New! Specify a maximum text-length, in characters, of a snippet for your page.
"max-video-preview:[number]" - New! Specify a maximum duration in seconds of an animated video preview
"max-image-preview:[setting]" - New! Specify a maximum size of image preview to be shown for images on this page, using either "none", "standard", or "large".
They can be combined, for example:
Preview settings from these meta tags will become effective in mid-to-late October 2019 and may take about a week for the global rollout to complete.
Using the new data-nosnippet HTML attribute
A new way to help limit which part of a page is eligible to be shown as a snippet is the "data-nosnippet" HTML attribute on “span”,”div”, and ”section“ elements. With this, you can prevent that part of an HTML page from being shown within the textual snippet on the page.
The ”data-nosnippet“ HTML attribute will start affecting presentation on Google products later this year. Learn more in our developer documentation for the robots meta tag, x-robots-tag, and data-nosnippet.
A note about rich results and featured snippets
Content in structured data is eligible for display as rich results in search. These kinds of results do not conform to limits declared in the above meta robots settings, but rather, can be addressed with much greater specificity by limiting or modifying the content provided in the structured data itself. For example, if a recipe is included in structured data, the contents of that structured data may be presented in a recipe carousel in the search results. Similarly, if an event is marked up with structured data, it may be presented as such in the search results. To limit that presentation, a publisher can limit the amount and type of content in the structured data.
Some special features on Search depend on the availability of preview content, so limiting your previews may prevent your content from appearing in these areas. Featured snippets, for example, requires a certain minimum number of characters to be displayed. This can vary by language, which is why there is no exact max-snippets length we can provide to ensure appearing in this feature. Those who do not wish to have content appear as featured snippets can experiment with lower max-snippet lengths. Those who want a guaranteed way to opt-out of featured snippets should use nosnippet.
The AMP Format
The AMP format comes with certain benefits, including eligibility for more prominent presentation of thumbnail images in search results and in the Google Discover feed. These characteristics have been shown to drive more traffic to publishers’ articles. However, publishers who do not want Google to use larger thumbnail images when their AMP pages are presented in search and Discover can use the above meta robots settings to specify max-image-preview of “standard” or “none.”
These new options are available to content owners worldwide and will operate the same for results we display globally. We hope they make it easier for you to optimize the value you get from Search and achieve your business goals. For more information, check out our developer documentation on meta tags. Should you have any questions, feel free to reach out to us, or drop by our webmaster help forums.