CiteTrue vs Zotero
Zotero is excellent at what it does: collecting references, keeping them tidy, and formatting them correctly. It is worth being clear that this is a different job from verification — Zotero will format a fabricated reference into flawless APA without complaint, because checking whether the work exists was never its role.
Why our verdicts hold up
Most citation checkers hand the whole judgement to a language model and show you what it says. Models hallucinate — that is the very problem this category exists to solve — so we put the model last, not first.
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1. Parse, don’t guess
Every reference is split into its parts — authors, title, year, journal, DOI — by a parser built for citation formats, not by asking a model what it thinks the title is.
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2. Look it up in the authorities
The parsed reference is queried against Crossref and OpenAlex, and against the open web when a reference has no DOI. What comes back are real records with real identifiers.
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3. Score the match deterministically
Candidate records are scored with a Sørensen-Dice similarity over title tokens. A record counts as a match only if the title score clears 0.7 and the author list agrees — a year mismatch is reported as a notice, never quietly accepted. The same reference always produces the same score.
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4. Only then, ask a model
A language model is called only when the deterministic pass finds no authentic match — to read the candidates and the source text and decide whether anything fits. It is the fallback, not the judge. That ordering is why a hallucinated verdict has nowhere to enter: by the time a model is involved, the evidence is already on the table.
The practical consequence: a reference marked authentic here matched a real record on title and authors, and you can open that record. It is not a model's impression of whether the citation looks plausible.
How fast it gets through a bibliography
Checking one reference means several lookups across different sources. Doing that one reference at a time is what makes a tool feel slow on a long bibliography, so we run them in parallel and stream the results back.
- References checked in parallel
- 20 at a time in the app, 100 through the API
- A 50-reference bibliography
- Goes out as three waves of parallel lookups, not fifty queued ones
- Results as they land
- Streamed per reference — you read the first verdicts while the rest are still running
- Bulk work
- A supervisor’s stack of theses runs through the API at five times the app’s concurrency
Different jobs, compared
| What you are comparing | CiteTrue | Zotero |
|---|---|---|
| What it is built for | Checking whether references are real and correctly cited | Storing, organising and formatting references |
| A fabricated reference typed in by hand | Flagged, with the reason | Formatted perfectly, silently |
| References pasted from an AI draft | Checked one by one against the literature | Imported as-is if a DOI resolves; otherwise typed in manually |
| Citation formatting | Not our job — keep using Zotero for this | Thousands of styles, done well |
| Cost | Free for 30 a day, then from $5.99/mo | Free, open source; paid storage |
| Convenience | Paste a bibliography, or check from the browser extension | Desktop app plus browser connector |
So which should you use?
These are complements, not alternatives. Zotero keeps your library in order; CiteTrue tells you whether what is in it is real. If your references came out of an AI tool, run them through CiteTrue before they ever reach your library.
Check your references now
30 references a day, free, no card. Paste a bibliography and see for yourself.