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BibTeX Validator

Upload a .bib file to check syntax, missing fields, dead DOIs, and verify your citations actually exist - useful for catching AI-hallucinated references. Files are never stored.

Drag a .bib file here, or click to choose. Max 2 MB.

Checks to run

Enabling DOI or database checks will send entry titles and authors to external services (doi.org, CrossRef, Semantic Scholar).

Files are never written to disk or logged.

How to validate a BibTeX file online

  1. Drag your .bib file onto the upload area, or click to choose it (up to 2 MB).
  2. Syntax and required-field checks run automatically. Optionally enable DOI resolution and/or database checks to catch hallucinated citations.
  3. Click Validate .bib. A color-coded table shows the status of each entry. Download the annotated .bib with inline warning comments for your editor.

About this tool

This tool validates BibTeX files in four layers: syntax + completeness (always), DOI resolution (opt-in), and title existence checks against CrossRef and Semantic Scholar (opt-in). It's particularly useful for catching AI-hallucinated citations that have plausible-looking metadata but don't correspond to real papers.

Can it detect AI-hallucinated citations?
Yes. Enable the CrossRef and/or Semantic Scholar checks. For each entry with a title, the tool queries the database and reports how closely the title matches a real paper. Low-confidence matches (below 50%) are flagged as likely hallucinations.
Are my files stored?
No. Your .bib file is validated in an ephemeral container and discarded immediately. When you enable DOI or database checks, titles and authors are sent to those external services - this is disclosed before you run the check.
What does the annotated .bib contain?
Your original .bib file with a comment line above each entry showing its validation status: missing required fields, DOI result, and database confidence scores. Paste it straight back into your editor.
What BibTeX entry types are supported?
article, book, inproceedings, proceedings, phdthesis, mastersthesis, techreport, misc, incollection, inbook, booklet, manual, conference, unpublished, and thesis.

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