The free Altmetric It! Bookmarklet is available from the altmetrics data provider, Altmetric.com or simply Altmetric.
The bookmarklet allows you to discover the volume and nature of online attention to a single research output, such as a journal article.
Watch this ~45 second video for how to install and use the Altmetric It! bookmarklet:
Tip: If the bookmarklet is not displaying an attention page, use your cursor to highlight the DOI on the webpage and try again.
Another tool is the Altmetric Badges, which can be implemented on a researcher's personal website to highlight their accomplishments and research impact.