Direct comparison
i10-Index vs. h-Index: What Each One Measures
The i10-index counts publications with 10+ citations; the h-index blends productivity and impact. Only Google Scholar reports the i10-index.
Side-by-side comparison
| Dimension | h-index | i10-index |
|---|---|---|
| What it measures | Largest h such that h papers each have at least h citations -- productivity and impact combined | Count of papers with 10 or more citations each -- a pure fixed-threshold count |
| Calculation method | Sort papers by citation count descending; find where paper rank is less than or equal to citation count | Count papers with citation count of 10 or more -- no sorting or self-referential condition |
| Threshold behavior | Self-scaling -- the bar rises as an author accumulates more highly-cited papers | Fixed at exactly 10 citations, identical for every researcher, field, and career stage |
| Introduced | 2005, by physicist Jorge Hirsch (PNAS) | 2011, by Google, alongside Google Scholar Citations profiles |
| Databases that report it | Google Scholar, Scopus (Author Details), Web of Science (ResearcherID) | Google Scholar only -- not computed by Scopus or Web of Science |
| Sensitivity to one blockbuster paper | Low once h is set by other papers -- one extra highly-cited paper adds little further | Also low, but differently -- a paper with 10 citations counts the same as one with 10,000 |
| Sensitivity to field / career stage | High, though the self-scaling condition partly compensates within a field | Higher -- a fixed 10-citation bar is far easier to clear in high-citation-density fields |
| Time behavior | Monotonically non-decreasing (can only grow or stay flat) | Monotonically non-decreasing (can only grow or stay flat) |
| Reported windows on Google Scholar | Lifetime figure and a rolling 5-year "Since [year]" figure | Same convention -- lifetime and rolling 5-year figures shown together |
| Responsible-assessment guidance | DORA, Leiden Manifesto, CoARA, Hong Kong Principles caution against use in hiring/promotion/funding | Same caution applies, though it is less often named explicitly in these frameworks |
| Typical appearance to a research administrator | Cited in CVs, biosketches, tenure dossiers; sometimes a specific database is required | Usually shown alongside h-index on a self-reported Google Scholar Citations profile |
Common questions
FAQ
Which is a better metric, h-index or i10-index?+
Neither is inherently "better" -- they answer different questions. The h-index blends productivity and impact into one self-scaling number; the i10-index is a plain count against a fixed threshold. Responsible-assessment frameworks such as DORA and the Leiden Manifesto caution against relying on either alone for hiring, promotion, or funding decisions.
Why is my i10-index so different from my h-index?+
They apply different rules to the same citation list, so a mismatch is expected, not an error. A researcher with a few very highly-cited papers and many lightly-cited ones can have a high i10-index (many papers individually clear the 10-citation bar) alongside a comparatively modest h-index, or the reverse, depending on the shape of the citation distribution.
Does Scopus or Web of Science report an i10-index?+
No. The i10-index is a Google Scholar-specific feature introduced in 2011. Scopus Author Details and Web of Science ResearcherID pages report an h-index and total citation counts, but neither computes or displays an i10-index.
Can I compare my i10-index to a colleague’s if we work in different fields?+
Not reliably. Neither metric is normalized for field-level citation density or career stage, and the i10-index’s fixed 10-citation threshold makes it especially sensitive to those differences -- a solid publication record in a lower-citation-density field may clear the bar far less often than the same record would in a high-citation-density one.
