Understanding Conference and Journal Rankings: CORE, h5-index, and What They Actually Measure
Two metrics come up constantly when researchers try to judge a venue’s standing: CORE rankings for conferences and h5-index for both conferences and journals via Google Scholar. Both get treated as shorthand for quality, and both measure something narrower than that.
What CORE actually ranks
CORE is a ranking system, mostly used in computer science and related fields, that categorizes conferences into tiers (A*, A, B, C) based on expert assessment of submission quality, acceptance rates, and community standing. It’s a reputation signal built through peer evaluation, not an automated metric, which makes it more subjective than it sometimes gets treated as, but also grounded in field-specific expert judgment.
What h5-index measures instead
Google Scholar’s h5-index counts how many papers from a venue, published in the last five years, have each received at least that many citations. It’s a pure citation-volume metric, useful for gauging a venue’s actual research impact over time, but blind to review rigor, since a venue can accumulate high citations through volume alone rather than exceptional individual work.
Why the two can disagree
A tightly curated A*-ranked conference in a small subfield might have a modest h5-index simply because the field itself is small, while a high-volume, broader-scope venue posts stronger raw citation numbers without matching selectivity. Neither number alone tells the full story, which is part of why serious evaluation looks at both alongside indexing status.
How to actually use these numbers
For CS and related fields, CORE rankings are a useful first filter when comparing conferences you’re less familiar with. For citation impact specifically, h5-index via Google Scholar’s metrics tool is the more direct number. Combined with checking indexing directly, see our piece on verifying Scopus-indexed conferences, these three checks together give a much fuller picture than any single metric alone.