You finished the manuscript. The citations are all there — written by hand, one by one — and now the journal, your committee, or your co-author wants them in a different style. And everyone's first advice is the same: "just use Zotero." Which is excellent advice for the next paper, and useless for this one: reference managers format citations they captured while you were writing. They cannot retroactively adopt the two hundred citations already sitting in your Word document.
Here is the direct answer, then the honest comparison of your real options.
If you don't use a reference manager (Zotero, Mendeley, EndNote), you can still convert your document's citation style: upload the .docx to a document-level converter like DEEPNOTIS, which reads the citations already in your file — footnotes, endnotes, or in-text (Author, Year) with a reference list — and re-renders them in any of 2,800+ styles. No library to build, nothing to retype, no account needed to try.
| Option | Time for ~80 references | Error risk | Works on your existing .docx? |
|---|---|---|---|
| Reformat by hand | Several hours to days | High — inconsistencies are exactly what copy-editors flag | Yes, painfully |
| Adopt Zotero/Mendeley retroactively | Days (re-enter or re-import every source, then re-insert every citation) | Medium — mismatched duplicates, lost locators | No — you rebuild the document's citations from scratch |
| Document-level conversion (DEEPNOTIS) | Minutes to an hour depending on how much you let the AI do | Low — every entry re-rendered from one structured record | Yes — that's the whole point |
A note of fairness: if you're starting a PhD or a long research project, do adopt a reference manager. Zotero is free, open-source, and outstanding at what it's designed for — capturing sources as you read and formatting them as you write. The gap it doesn't cover is the one this article is about: the document that already exists.
Zotero, Mendeley and EndNote work through a Word plugin that inserts live fields — placeholders linked to entries in your personal library. Formatting flows from library → field → document. If your citations were typed by hand, there are no fields and no library: the manager has nothing to hold on to. The official workaround is to rebuild everything: add each source to the library, then delete each typed citation and re-insert it through the plugin. For a thesis, that is genuinely days of work, with plenty of opportunities to drop a page number along the way.
Document-level converters invert the logic: instead of asking you to rebuild your citations inside a manager, they read the citations you already wrote.
The structured records are yours afterwards: export them as BibTeX or RIS and import into Zotero for your next paper — the two approaches are complements, not rivals.
One honest caveat. Converting an author-date manuscript (APA) to another author-date style (Harvard) is fully automatic — the reference list re-renders and your (Author, Year) markers stay valid. Converting across families — say (Author, Year) in-text to Vancouver's numbered [1] markers — requires rewriting the body text itself, which no tool currently automates well; footnote- and endnote-based documents, whose markers Word manages natively, can already target any of the 2,800+ styles.
Can I change citation style in Word without any add-in or software? Only by hand. Word has a built-in citation tool, but like Zotero it only formats citations it inserted — it can't adopt citations you typed.
Does conversion work if my citations are slightly inconsistent? Yes — that's the normal case for hand-written citations. Each citation is parsed into structured fields, and inconsistencies (a missing year, a mistyped author) surface visibly for review instead of silently propagating.
Is my manuscript safe? With DEEPNOTIS, documents are processed in a private pipeline and never sent to external AI services; the citation analysis is deterministic. You can delete your data at any time, and guest uploads are automatically purged after seven days.
How much does it cost? The check and preview are free (3 documents/month, no card). A one-time £6 unlock exports a single fully-formatted document — with an invoice, for lab reimbursement. Subscriptions exist for recurrent use.
Need the reverse workflow — you already use a reference manager and want your library out of it? See our guides on converting between citation formats (BibTeX ↔ RIS ↔ CSL-JSON). Ready to convert a document? Upload it here — no account needed.