H-Index Calculator (Hirsch Index)
Paste your per-paper citation counts to instantly compute the h-index (Hirsch 2005 — the most widely cited measure of scholarly impact), g-index (Egghe 2006 — emphasising highly cited work), i10-index (Google Scholar profiles), plus total, mean and median citations. Works with any Google Scholar, Scopus, Web of Science or ORCID export.
Enter at least one valid citation count (a non-negative integer). Separate values with commas, whitespace or new lines.
h-index
—
Hirsch index: h papers each cited at least h times.
g-index
—
Egghe index: top g papers together accrue ≥ g² citations. Weighted toward highly cited work.
i10-index
—
Number of papers with ≥ 10 citations (used by Google Scholar profiles).
Total papers
—
Total citations
—
Mean citations
—
Median citations
—
Max citations
—
Formula
h = max { k : the k-th most-cited paper has ≥ k citations }
Sort papers by citations in descending order; h-index is the largest k such that the top-k papers each have ≥ k citations. The same researcher generally has different h-indices across Google Scholar, Scopus and Web of Science because the databases index different journals — compare like-for-like.
Formula
h-index: sort papers by citations (descending); h = max { k : the k-th paper has at least k citations } g-index: g = max { k : the top k papers have at least k² citations in total } i10-index: count of papers with at least 10 citations
- · h-index captures both breadth and depth: you need h papers each cited at least h times. A single mega-hit cannot pull it up, and many ignored papers cannot drag it down.
- · g-index ≥ h-index always. When a few papers attract disproportionately many citations, g exceeds h — better recognising standout work.
- · i10-index was introduced by Google Scholar profiles. It is just the count of papers with ≥ 10 citations, with no upper bound on citation distribution.
- · The same researcher typically has different h-indices in Google Scholar, Scopus and Web of Science because each database indexes a different set of journals, conferences, books and preprints (GS the broadest, WoS the most restrictive).
- · Compare like for like across fields: bio-medical and high-energy physics produce naturally high citation counts, while mathematics, humanities and most engineering fields run far lower. Use field-and-career-stage normalisation before cross-discipline comparison.
- · Self-citations inflate h-index. Serious evaluations (e.g. tenure committees) usually request the h-index after self-citations are excluded (hₐ).
- · This tool silently skips negative or non-numeric tokens; fractional citation counts are floored. Data is processed entirely in your browser — nothing is uploaded.
- · References: Hirsch JE, PNAS 102(46) 16569–16572 (2005); Egghe L, Scientometrics 69(1) 131–152 (2006); Google Scholar Help — profile metrics.
Frequently asked
Why do I get different h-indices on Google Scholar vs Scopus?
The databases index different things. Google Scholar is the broadest — it sweeps in books, articles, preprints, theses, conference papers and grey literature, so citation totals and h-index are usually highest there. Scopus and Web of Science only index peer-reviewed journals and proceedings, so they yield fewer citations. As a rough rule of thumb, the same researcher's Google Scholar h-index is 1.3–2× their Web of Science h-index. Always state which database an h-index came from.
Why is my h-index so low as a PhD student or early-career researcher?
h-index has a strong time bias: each paper needs several years to accumulate citations before contributing to h. Empirically, h grows roughly like 0.4 N to 0.5 N (with N the career length in years), so a PhD graduating with h = 1–4 is completely normal. The m-quotient (h ÷ academic age) was proposed by Hirsch specifically to compare researchers at different career stages without penalising the young.
What are the limits of h-index? Should hiring or tenure rely on it?
h-index should never be used in isolation for evaluation. Common criticisms: (1) insensitive to outliers — a paper with 10,000 citations contributes the same to h as one with 100; (2) it strongly depends on field, career length and co-authorship patterns; (3) it cannot distinguish lead authors from coauthors; (4) it incentivises "salami slicing." The Leiden Manifesto (2015) and the San Francisco Declaration on Research Assessment / DORA (2012) both recommend treating h-index as one signal among many — alongside peer review, originality and qualitative judgement.
Can I exclude self-citations?
Yes. Use the "exclude self-citations" filter in Scopus or Web of Science, or manually subtract self-citations from each row in Google Scholar before pasting them in here. Excluding self-citations typically reduces an h-index by 5–25 %, with the larger reductions in fields where co-author chains are long (e.g. high-energy physics).
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