The most well-known author-level metric is the h-index although there are several other variants. The h-index is a measure of both productivity and impact. It looks at the total number of papers you have published, and the number of citations these papers have received.
For example, if you've published 2 papers, and each paper has been cited 2 times, you will have a h-index of 2.
What if it's a little more complicated, where your published papers have range of both high and low citations? Let's say you've published 5 papers altogether, one cited 5 times, one 4 times, one 3 times, one 2 times, and one just the 1 time. You will have a h-index of 3. That is to say, you cannot claim higher (4 papers cited 4 times each).
Thus the h-index attempts to measure the impact of your output - you need to have published a large number of papers, which were in turn cited a large number of times, to have a high h-index.
Limitations of h-index
The h-index is not appropriate for comparing across disciplines and disadvantages early career researchers.The following graphic shows a richer narrative of one academic's work than is represented by the -h-index
The h-index is on the author's profile page.
Hover over the ? for more information about the h-index and click on view to see the full graph.
A date filter and self-citations exclusion can be applied to the graphic.
Search Publons to find the h-index for a researcher in the Web of Science Core Collection. The h-index for this researcher is 18.
In Google Scholar, the same author has the following information.