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Check the citation before you trust it.

Paste a reference list. Every entry is looked up in Crossref, OpenAlex, arXiv and PubMed, then compared field by field against the indexed record — authors, title, source, year, DOI. You see exactly what matched and what didn't.

Built for the moment a reference looks plausible, reads well, and you still can't find it anywhere.

Works on a whole reference list, not one entry at a time.
Open scholarly metadata only. No scraped or resold data.
Nothing you paste is stored unless you ask us to save it.

Evidence first. Conclusions second. See how verification works

Citation checker

Five honest answers, not one misleading score

A citation can look correct and still point to the wrong paper. Every check ends in one of five clearly defined states — with the evidence shown, so you can judge for yourself.

What each result means

Verified
The citation appears to correspond to a real record, and its important details substantially agree. It does not mean the source is high quality, unretracted, or that it supports your claim.
Partial match
A likely related record exists, but one or more important fields differ — a wrong year, different authors, or a DOI pointing at a different paper.
Needs review
The evidence is incomplete, ambiguous, or conflicting. A human needs to look at the source.
Not found
The enabled sources returned no adequate record. Not found does not automatically mean fake — coverage, spelling, indexing delays, and non-scholarly sources all affect results.
Service unavailable
A data provider failed or timed out, so the check could not be completed. This says nothing about the citation itself.

How verification works

Parse

Your citation is split into structured fields — title, authors, year, venue — and scanned for identifiers such as DOIs, PMIDs, and arXiv IDs.
Resolve & search

Identifiers are resolved first, because they are the strongest evidence. Without one, the bibliographic details are searched across scholarly metadata providers.
Compare

The returned record is compared field by field with what you submitted. Meaningful differences are preserved, not smoothed over.
Show the evidence

You see the matched record, the comparison, the sources checked, and the limitations — enough to understand the result, not just accept it.

No language model invents or “corrects” bibliographic facts anywhere in this pipeline. Read the full methodology.

Checked against real scholarly records

CitationCheck queries public scholarly metadata services. Each has genuine strengths and genuine gaps — no single source covers everything, and we say so.

Crossref DOI registration metadata for most journal articles, books, chapters, and conference papers registered with Crossref.
OpenAlex Broad open catalog of scholarly works, including many items without Crossref DOIs.
arXiv arXiv preprints in physics, mathematics, computer science, and related fields.
PubMed (NCBI E-utilities) Biomedical and life-science literature indexed in PubMed (PMID resolution).

Querying a public API is not a partnership or endorsement. Monographs, legal citations, grey literature, and subscription indexes such as Scopus or Web of Science are not covered. Coverage and limitations, per source.

Who this helps

Students & educators

Check a bibliography before submission — or before grading it — and see exactly which references need a second look.

Researchers & editors

Screen reference lists for malformed, mismatched, or unresolvable citations before review, not after publication.

Librarians & reviewers

Get a fast, transparent first pass on whether a reference resolves to a real record — with the evidence to verify the tool's work.

Citation checking works best as a routine habit, and habits don't form behind paywalls. Basic checks are free, anonymous, and stay that way.

If you'd like to hear when new capabilities land — saved check history, exports, retraction flags — leave an email. That's all it's for, and it's entirely optional.

Common questions

Does “Not found” mean the citation is fake?: No. Not found means the sources we query returned no adequate record. Coverage gaps, unusual spelling, indexing delays, non-scholarly sources (like newspapers or webpages), and incomplete details can all cause a real work to go unfound. Treat Not found as a prompt to check the original source, not as a verdict.
Does “Verified” mean the source is good?: No. Verified means the citation appears to correspond to a real record and its important bibliographic details substantially agree. The paper could still be weak, irrelevant, corrected, retracted, or misused in your argument. Verification checks the record. Human review checks the meaning.
Which sources do you check against?: Currently Crossref, OpenAlex, arXiv (for arXiv IDs), and PubMed (for PMIDs). Each has real coverage limits, described on the Data Sources page. No source covers everything, and we do not claim to search “the entire academic internet.”
Do you store what I paste?: Submissions are processed in memory and discarded after the response. Provider responses are cached briefly (keyed by a hash of the query) to reduce load. Full pasted text is not written to routine logs.

All frequently asked questions