Reference and bibliography checker
Broken references - citations with no matching bibliography entry, entries with dead DOIs, or titles that do not correspond to any real publication - undermine a paper's credibility. They are easy to introduce and hard to catch by eye.
Quick answer
To validate references, confirm every \cite has a matching .bib entry (no undefined [?] citations), and verify each DOI and title against a source database. LaTeX Formatter checks your bibliography against CrossRef, flags dead DOIs and unverifiable titles, and reports how many citations it could confirm.
What goes wrong with references
Citation keys drift out of sync with the .bib file, producing undefined references that compile to a bold [?].
Bibliography entries carry incorrect or dead DOIs, or titles copied with errors.
Entries generated by AI tools may look complete but reference publications that do not exist.
How to check references manually
Read the LaTeX log for 'Citation undefined' and 'There were undefined references' warnings.
Spot-check DOIs and titles against the source databases.
Confirm every \cite key has a matching entry in the .bib, and that no entries are duplicated.
How LaTeX Formatter validates references automatically
When you include a .bib, LaTeX Formatter runs citation verification against CrossRef, flags dead DOIs and titles that cannot be found, and reports the count of verifiable citations.
It runs for every document type when a .bib is present, so theses and reports get the same reference check as conference papers.
Who this helps
- Authors with long reference lists
- Thesis writers citing across chapters
- Anyone consolidating multiple .bib files
Frequently asked questions
Why does my citation show as [?] in the PDF?+
The \cite key has no matching entry in your .bib, or BibTeX/Biber did not run. Confirm the key exists and re-run the bibliography pass.
Do you check references without a .bib file?+
Reference verification needs the .bib to read the DOIs and titles. If you cite sources but upload no .bib, LaTeX Formatter reports that it could not verify your references rather than passing silently.
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