The h-index is a metric that is used to quantify the impact of a researcher’s work. It was first proposed by physicist Jorge Hirsch in 2005 as a way to measure the productivity and citation impact of scientists.
The h-index is based on both the number of publications a researcher has and the number of times those publications have been cited by others. Specifically, the h-index is the highest number of publications by a researcher that have each been cited at least that same number of times.