Questions
Frequently asked questions
Short answers about results, coverage, and privacy. If yours isn't here, the contact address is in the footer.
- What does Verified mean?
- The citation's identifier (if present) resolves to a real scholarly record, the title substantially agrees, no field critically contradicts the record, and the citation carried enough detail — typically title plus authors — to corroborate the match. Verified is deliberately difficult to earn: when evidence is ambiguous, you get Needs review instead.
- Does Verified mean the source is credible?
- No. Verified means the bibliographic information corresponds to a real record. The paper could still be weak, superseded, corrected, retracted, or irrelevant to the claim it supports. Verification checks the record; human review checks the meaning.
- Why did CitationCheck return Needs review?
- Usually one of three reasons: the citation conflicts with the record it points to (for example, a real DOI and title with different authors — a common pattern in corrupted or generated citations); the citation is too sparse to corroborate a match (a bare DOI or a title alone); or a data provider was unavailable, so coverage was incomplete. The card always states which.
- Does Not found mean the citation is fake?
- No. Not found means the enabled sources returned no adequate record. Coverage gaps, unusual spelling, indexing delays, non-scholarly sources (newspapers, webpages, reports), and incomplete details can all cause a real work to go unfound. Treat it as a prompt to check the original source.
- Why wasn't my citation found?
- The most common causes: it isn't a scholarly work (news, blogs, standards, and most books aren't well covered); the title or authors contain errors that defeat search; it's very recent and not yet indexed; or it's in a source the enabled providers don't cover, such as regional publishers or subscription-only indexes.
- What citation styles are supported?
- Parsing is style-tolerant rather than style-specific. APA-like references parse best; numbered lists ("[12] …"), quoted titles, and identifier-only lines also work. Any reference containing a DOI, PMID, or arXiv ID gets the strongest treatment, since identifiers are extracted regardless of formatting.
- Can I paste references generated by ChatGPT or Claude?
- Yes — that is a primary use case. Generated references often combine a real identifier or title with wrong authors, years, or venues. Those hybrids classify as Partial match or Needs review, with the conflicting fields shown, rather than being waved through.
- Which academic data sources does CitationCheck use?
- Crossref and OpenAlex for identifier resolution and bibliographic search; PubMed for PMIDs; arXiv for arXiv IDs. Each has real coverage limits, described on the Data Sources page. No source covers everything, and provider use does not imply endorsement.
- How are authors compared?
- By normalized family name overlap, with particle surnames (van, von, de…) kept intact, diacritics normalized, and "et al." respected — only the listed authors are compared, and author counts aren't penalized. The card reports agreement plainly, e.g. "2 of 3 cited authors found in the record's author list."
- How are publication years handled?
- A difference of ±1 year is tolerated (±2 where a preprint is involved), because online-first publication and indexing genuinely shift years. A gap of more than 3 years is treated as a version or publication mismatch and blocks Verified.
- How are preprints handled?
- An arXiv preprint and its published journal version are related but different records. When a preprint is involved, venue differences are softened and year tolerance widens — and the card shows the record's details so you can see which version you're actually citing.
- What happens if Crossref or another provider is unavailable?
- The result is Service unavailable — never Not found. Provider failure says nothing about your citation, and the card names which providers had problems. If some providers responded but nothing was found, the result is Needs review with the incomplete coverage stated.
- Does CitationCheck save my references?
- No. Submissions are processed in memory and discarded after the response; pasted text is not written to routine logs. Provider responses are cached briefly (keyed by a hash of the query) to reduce load. The optional email signup is the only user information the site collects.
- How do I report an incorrect result?
- Every result card has a "Report an incorrect result" link. Email the citation and, if you have it, the DOI or a link to the correct record. These reports directly drive parser and threshold fixes.
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