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Quick answer: to look up an h-index, open the researcher’s profile in Google Scholar Citations (free, if the person made a profile), the Scopus author details page, or a Web of Science Citation Report. Each shows its own number, because each counts a different set of papers and citations. Pick one database, check that the profile really is the right person, and always say which database the figure came from.
What an h-index is
A researcher has index h if h of their papers have each been cited at least h times and the remaining papers have no more than h citations each (Hirsch, 2005, PNAS). Papers are ranked from most to least cited; c is a paper’s citation count; the h-index is the largest rank at which c is still at least equal to the rank. For the full definition and context see h-index in the CASRAI dictionary.
How to look up an h-index in Google Scholar
Google Scholar Citations computes two versions, All and Recent, of three metrics: h-index, i10-index and total citations. A profile is private until its owner makes it public, and to appear in Scholar search results it must be public and have a verified institutional email address (Google Scholar Citations help, read 2026-11-07).
- Go to Google Scholar and search the person’s name, or search a topic and follow author names that link to profiles.
- Open the profile and read the metrics box, which lists citations, h-index and i10-index in an All column and a Recent column.
- Confirm the publication list is theirs (see the checklist below).
If the researcher has no public profile, Google Scholar shows no h-index. To build your own, see how to create and optimize a Google Scholar profile.
How to find an h-index in Scopus
University library guidance (the RPI Libraries Scopus guide, read 2026-11-07) describes the route: open the Author Search tab, enter the name and optionally an affiliation, choose the correct entry, and read the h-index on the author details page, alongside publication and citation counts. Scopus access normally requires an institutional subscription. If one person’s papers are split across several entries (different affiliations, a missing middle initial), you cannot combine them yourself; the same guide says to submit a request to merge authors through the Scopus Author feedback wizard, after which the updated entry shows the new h-index. Menu labels can change between releases. See also how to create a Scopus Author ID.
How to find an h-index in Web of Science
University library guides (Emory, UCAR and Stony Brook, among others, searched 2026-11-07) describe two routes. For any author: run an Author search in the Core Collection (last name plus first initial), then choose Create Citation Report; the h-index appears in the report summary. For a researcher who has claimed a profile, the Researcher Profile lists publications and citation metrics. The guides stress that the result is only as accurate as the publication list you select, so remove papers by other authors who share the name before creating the report. Record selection and merging are covered in Web of Science author search. Web of Science normally requires an institutional subscription.
Free options
Google Scholar profiles are free to read. Scopus and Web of Science are subscription products, usually reached through a university or institute library. Free desktop software that queries several sources also exists (for example Publish or Perish, created by Anne-Wil Harzing), but its output depends on the source you choose, so label the figure accordingly.
Why the three numbers differ
| Database | Where the number is | Who controls the list of papers | Access |
|---|---|---|---|
| Google Scholar | Public author profile, metrics box | The researcher (adds and removes articles) | Free; profile must be made public |
| Scopus | Author details page | Automatic author matching; fixes by merge request | Institutional subscription |
| Web of Science | Citation Report from an Author search, or a Researcher Profile | Whoever builds the search or claims the profile | Institutional subscription |
Library guides consistently report that Google Scholar values are often higher than Scopus or Web of Science because Google Scholar covers more content with looser inclusion criteria. No value is wrong; they measure different corpora. The reasons in detail, and how to audit your own gap, are in how to calculate the h-index and the Google Scholar vs Scopus comparison.
Check you have the right profile
- Does the publication list match the person’s field, years and affiliation?
- Are there other entries for the same name? Split profiles understate the h-index.
- Does an ORCID iD, where listed, match the person?
- How recent is the figure? Citation counts change over time.
Verify it by hand: worked example
Take ten papers with these citation counts, sorted from most to least cited: 25, 18, 12, 9, 7, 6, 4, 3, 1, 0.
| Rank | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 |
|---|---|---|---|---|---|---|---|---|---|---|
| Citations | 25 | 18 | 12 | 9 | 7 | 6 | 4 | 3 | 1 | 0 |
| Citations at least rank? | yes | yes | yes | yes | yes | yes (6 = 6) | no (4 < 7) | no | no | no |
Rank 6 is the last rank where the citation count (6) is at least the rank (6), so h = 6. Rank 7 has only 4 citations, which is less than 7.
Excel, R and Python
Excel, with counts in A1:A10 sorted descending: =SUMPRODUCT(--(A1:A10>=ROW(A1:A10)-ROW(A1)+1)) returns 6.
R: x <- c(25,18,12,9,7,6,4,3,1,0); sum(sort(x, decreasing=TRUE) >= seq_along(x)) returns 6.
Python: c = sorted([25,18,12,9,7,6,4,3,1,0], reverse=True); h = sum(1 for i, v in enumerate(c, 1) if v >= i) gives 6.
Is my number good?
No single threshold applies. Hirsch (2005) proposed dividing h by career years to get a slope m. Drawing on physics, he described m of about 1 (h of about 20 after 20 years) as a successful scientist, about 2 as outstanding, and about 3 as truly unique. That scale was derived from physics, so it does not transfer automatically to other fields. The h-index also depends on the database. For benchmarks see what counts as a good h-index, and for the limits of using it in evaluation see the DORA declaration and h-index vs i10-index.
How to report it
State the database and the date, for example: “h-index = 6 (Scopus, accessed 7 November 2026).” Include the access date in the text or a table note, because the value changes over time.
Frequently asked questions
What is a good h-index in medicine?
No sourced threshold fits all of medicine, because subfields cite at very different rates. Compare against peers at the same career stage, in the same subfield and in the same database.
Which is better, Google Scholar or Scopus?
Neither is better for every purpose. Google Scholar is free and broader, but its profile is self-curated; Scopus is subscription-based and narrower. Choose by what the audience, such as a promotion committee, asks for.
How do I get my h-index from Google Scholar?
Sign in with a Google account, create a profile, add your articles, and read the h-index in the metrics box. Make the profile public if others should see it.
How can I find my h-index in Scopus?
Use Author Search, open your author details page and read the h-index; request a merge if your papers are split across entries.
Is an h-index of 12 good? Is 5 good for a PhD student? Is 200 good?
It depends on career length and field. Using Hirsch’s slope, h = 5 after 5 years is m = 1.0, and h = 12 after 12 years is also m = 1.0, which Hirsch described as a successful scientist in physics. An h-index of 200 lies far above the values Hirsch illustrated, which were derived from physics for individual careers, so read any such figure together with its database and the field.
What was Einstein’s h-index, and what is Elon Musk’s?
No figure is quoted here. Published values for named individuals vary by database and by which papers a profile includes, and for historical figures many works are not indexed. Look the person up in a database you can name and report the date.
Sources
- Hirsch, J. E. (2005). An index to quantify an individual’s scientific research output. PNAS, 102(46), 16569-16572. PMC1283832 (read 2026-11-07).
- Google Scholar Citations, scholar.google.com/intl/en/scholar/citations.html (read 2026-11-07).
- RPI Libraries, Scopus guide: author tools, guides.lib.rpi.edu (read 2026-11-07).
- Emory, UCAR and Stony Brook library guides on the Web of Science h-index (searched 2026-11-07).
