Google has recently made changes to the display length of snippets on the search engine results page. These snippets are the short blurbs that display what a website is about when you search for a keyword or phrase.
Previously maxing out at around 155 characters, the majority of snippets are now showing up to double that amount -- between 250 and 320 characters -- allowing websites to show even more descriptive text to help their visitors understand how their page is relevant in search results.
However, there are a few exceptions. As Moz.com posted, their extensive research into snippet length resulted in them finding a few anomalies:
Video snippets seem to max out at around two lines, under a 200-character count, and are further restricted by the remaining space that the thumbnail allows.
Any pre-truncated meta data like that updated automatically through CMS systems will override the new snippet character limit and show a shortened description.
Most interestingly, it now appears that if the original description is too short or not descriptive enough, Google will rewrite the meta description using a core piece of text from the page itself. For example, in searching for "Umami", the following result came up on the results page:
This snippet that has been displayed is 316 characters long, whereas the actual meta description tag on the page has only been entered as follows, and is only 188 characters:
Sour, sweet, salty and bitter have long been considered the four main flavors we can taste. Umami, a Japanese word that describes a meaty or savory taste, is thought to be a fifth flavor.
When visiting and reading the actual site, we can see that Google has taken a longer, more descriptive chunk of text from the web page itself, something Yoast refers to as a "core paragraph".
As this is a new change, there is still a lot of testing to be done to determine if this means that it might be more meaningful to delete meta descriptions entirely and instead rely upon Google to pull "core paragraphs", or if longer meta descriptions including searched-for keywords are still relevant. In the meantime, Yoast SEO has updated their WordPress plugin to only show an orange bullet if your meta description exceeds 320 characters, and will continue to run research to and keep us all aprised of any changes to best practices they may recommend.