BibTeX checker for Overleaf and Zotero
Paste a .bib file, from Overleaf, Zotero or anywhere else. Each entry is looked up in Crossref and comes back found, found with a different year or authors, or not found, and flagged if it has been retracted.
Up to 25 references a check, 3 checks a day.
How it works
Paste or upload
A reference list, a .bib or .ris file, or the whole draft as Word or PDF.
Each work looked up
In Crossref, where publishers register their papers, then OpenAlex for books and the rest, by DOI or by title, author and year.
See what to fix
Found, found with a different year or authors, or not found, and any retraction flagged.
Records from Crossref and OpenAlex; retractions from Retraction Watch, through Crossref. Nothing you paste or upload is kept.
Keep your library in Zotero?
Right-click items or a whole collection and choose Check references with hedwigai. The check opens here and starts at once. Free, for Zotero 7 and 8; nothing in your library changes.
How do I get the .bib file out of Overleaf?
Open the project, select the .bib file in the file tree (often references.bib), select all its text and paste it above. Or download the file from the file tree and upload it here.
And out of Zotero?
Easiest: install the hedwigai Zotero plugin, right-click the collection and choose Check references with hedwigai. Or select the collection, choose Export Collection, pick BibTeX, and upload the file above. Better BibTeX’s auto-export file works too. The free check reads the first 25 entries; check a large library a collection at a time.
What does it read from each entry?
The title, the first author’s family name, the year, the journal or booktitle, and the DOI. Braces that protect capitals, {{Deep}} learning, are read through. An entry with a DOI is checked by its DOI first, and a DOI registered to a different title is said.
What does the full check add?
Sign in and give hedwigai the paper itself, and every sentence that cites a work is read against it, with the passage that settles it. Writing in LaTeX with Claude Code, Cursor or Codex? The reference-checker skill (npx skills add un-seen/hedwigai-skills --skill reference-checker) has your agent turn the paper into text with its citations and run the check.