Altmetrics, or alternative metrics, is "the study and use of scholarly impact measures based on activity in online tools and environments" (Priem, Groth, and Taraborelli 2012). Altmetrics utilize new sources of data, based on online activity, to measure the impact of journals, authors and articles.
Altmetrics are meant to compliment, not replace, traditional measures of impact.
Examples of altmetrics include:
Altmetrics offer possible advantages over traditional citations because they:
The preceding statements were adapted from Altmetrics: A Manifesto, Bulletin of the Association for Information Science and Technology, PLoS Altmetrics Collection, and Plum Analytics.
Altmetric page for article published in British Medical Journal
Several databases and publishers provide article-level metrics. These metrics depend on the content that is searched. For example, the number of citations that an article has received in Web of Science will likely be different than the number it has received in either Scopus or Google Scholar.