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Research Impact and Author Profiles

What is the H-index?

  • The H-index is a measure of an individual's impact on the research community based upon the number of papers published and the number of citations these papers have received.       

Image source: h-index from a plot of decreasing citations for numbered papers, Public Domain

The index was first proposed by J. E. Hirsch in 2005 and is defined as:

A scientist has index h if h of his/her Np papers have at least h citations each, and the other (Np-h) papers have no more than h citations each. As an example, a researcher with an H-index of 15 has (of their total number of publications) 15 papers which have been cited at least 15 times each.

An index to quantify an individual's scientific research output

J.E. Hirsch's original article in which the h-index was proposed, published in Proceedings of the National Academy of Sciences of the United States of America. 2005; 102(46):16569-16572.

Limitations and considerations

There are a number of limitations and cautions to be taken into account when using the H-index. These include:

  • Academic disciplines differ in the average number of references per paper and the average number of papers published by each author. The length of the academic career will impact the number of papers published and the amount of time papers have had to be cited. The H-index is therefore a less appropriate measure for junior academics.
  • There are different patterns of co-authorship in different disciplines. Individual highly cited papers may not be accurately reflected in an H-index.

Calculating Your H-index

The H-index can be calculated using the University of Toronto Library-subscribed databases Web of Science or Scopus, using Scoups free author lookup, or  also using the My Citations feature of Google Scholar or the freely downloadable program Publish or Perish, which also takes its citation information from Google Scholar.

However if you wish to create a true H-index based on all unique citations to your publications from all sources, you will need to calculate it manually.  The fewer papers you have the more significant each citation becomes in terms of calculating your H-index. Please contact Information Specialists for more information on this process.

Tools for Determining H-Index:

Scopus provides citation tracking and a number of other visualization and analysis tools. Scopus is particularly useful for citations in the Sciences


  • Start with author search, select your name (you may appear more than once)
  • Show documents
  • Add to list
  • Search and add missing publications to list, if necessary
  • When this temporary list is complete, view list, select all
  • View citation overview. This will give you your career h-index. The date range is for the graph only!
  • To calculate your 3, 4, or 5 year h-index, go back to your list and select the appropriate years of publication i.e. for last 3 years, choose publications from 2016, 2015, 2014, (2013 ) and view citation overview

Web of Science tracks citations across the Sciences, Social Sciences, and Humanities, and includes conference proceedings as well. The Web of Science is particularly useful for citations in the Sciences.


  • Choose author search from the drop-down menu, fill in the details. If you’ve published under variations of your name (e.g. with and without your middle initial, be sure to search on author variant name.
  • View author sets, select yours, add to marked list
  • View marked records, scroll down to see publications, create citation report

Google Scholar is useful for finding citations in books, grey literature, government and legal publications, and non-English resources. Google Scholar also indexes journals in the Sciences, Social Sciences, and Humanities, though the scope of this is unknown.


  • Follow the steps to create your Google Scholar “My Citations” author profile and it will generate your h-index.
  • The 5 year h-index calculates your score from citations made within the last 5 years to all of your publications. Note that Web of Science and Scopus calculates the 5-year h-index from the citations to the articles you have published over the last 5 years.

If you do not have a "My Citations" Profile, you can download the Publish or Perish software to calculate your Google Scholar h-index.

Read more about the H-index:

A commentary on the h-index by Professor Ann-Wil Harzing of the University of Melbourne (2008). Also discusses other indicies used to calculate researcher impact.

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