Zotero vs Mendeley

Zotero and Mendeley both keep a research library, but they earn their money in different places. Zotero charges only for attachment storage, with 300 MB free and unlimited data syncing, and it is described as a project of the nonprofit Digital Scholar. Mendeley's current pricing page sells an AI workspace called LeapSpace at EUR 24 a month, and the cost of the plain library is not shown there. The pages we read name no owner for Mendeley, so the choice comes down to storage fees versus an AI subscription, and to how much vendor independence you want.

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Both are reviewed in full in our reference management software ranking: Zotero and Mendeley.

1. 01

   What 300 MB buys against a 14-day taste

   Zotero gives 300 MB of file storage free, with no end date, and the storage page mentions no trial because none is needed. Mendeley's free route is 'Try LeapSpace for free' at EUR 0 with no credit card, where the starred features are unlimited for 14 days and then limited. One is a permanent small allowance, the other a short window before limits arrive. For a student who just wants to keep a library alive, Zotero's open-ended free tier is the safer starting point.

   Edge: Zotero

2. 02

   Yearly storage tiers versus a EUR 290 annual plan

   Zotero's storage plans run 2 GB at $20 per year, 6 GB at $60 and Unlimited at $120, about $1.67, $5 and $10 per month. Mendeley's LeapSpace Individual plan costs EUR 24 per month or EUR 290 billed every 12 months, and it includes the Mendeley AI features. These are different purchases: Zotero sells file space, Mendeley sells AI access. On raw cost for a growing PDF collection, Zotero's Unlimited tier is far below the Mendeley yearly figure.

   Edge: Zotero

3. 03

   Asking your own PDFs questions

   Mendeley's paid plan adds Ask My Library, which searches, summarises and compares the PDFs you saved, and a Reading Assistant that explains any document. File Upload takes up to five PDFs per conversation, which is the only file limit the page states. Zotero's pages we read describe collecting, organising and citing, and they do not show an AI question tool. If summarising papers is the reason you are buying, Mendeley alone lists such a feature in the text we read.

   Edge: Mendeley

4. 04

   Who is behind the roadmap

   Zotero is shown in its footer as a project of Digital Scholar, which the site calls a nonprofit, and the site traces its origin to George Mason University's Roy Rosenzweig Center for History and New Media. For Mendeley, the homepage names no owner, operating company or country, and it links onward to a LeapSpace page on sciencedirect.com. The Elsevier about page we read does not mention Mendeley either. Zotero is the one whose governance can be read from its own pages.

   Edge: Zotero

5. 05

   Word, LibreOffice and Google Docs citing

   Zotero lists citation support for Word, LibreOffice and Google Docs, with over 9,000 citation styles, and it saves research automatically while you browse. It also offers collections, keyword tags and saved searches. Mendeley's pricing page mentions a Word add-in as part of the plan, and says nothing about LibreOffice or Google Docs in the text we read. A writer who switches between word processors will find Zotero's stated coverage wider, and its style count is a number the other page does not give.

   Edge: Zotero

6. 06

   Group libraries and corporate buyers

   Zotero says shared libraries can be created at no cost, though group files draw on the group owner's storage account, and institutions and labs have separate plans with no prices shown. Mendeley's organisation plan is priced on request through sales and shows unlimited access for eligible researchers, with storage not stated. Mendeley also states that its individual plans are not for corporate use. A lab wanting a quote and a contact will find Mendeley's route more formal, while a small group will manage on Zotero.

   Depends on the buyer

What happens to my attachments once Zotero's 300 MB is full?

Items, notes and tags keep syncing, because data syncing is free and unlimited.

Only the files stop syncing until you buy a 2 GB, 6 GB or Unlimited plan, or point Zotero at a WebDAV server of your own. The storage page we read lists those paid tiers at $20, $60 and $120 per year.

Is there still a zero-cost way into Mendeley?

The upgrade page we read lists an Individual entry called 'Try LeapSpace for free' at EUR 0 with no credit card.

Its starred features are unlimited for 14 days and limited afterwards. The page does not say what the plain library costs or how much storage it includes.

Who runs Mendeley today?

The Mendeley homepage we read does not name an owner, operating company or country, and the Elsevier about page does not mention Mendeley.

The pricing URL redirects to a researcher.elsevier.com page, which is the only link between the two that we saw. We therefore state no ownership beyond that redirect.

• Zotero storage page: the 300 MB free tier and the $20, $60 and $120 yearly storage plans.
• Zotero homepage: 9,000 styles, three word processors, free shared libraries, optional sync on AWS.
• Zotero about page: nonprofit Digital Scholar project and George Mason origin.
• Mendeley upgrade page on researcher.elsevier.com: the EUR 0 trial, EUR 24 and EUR 290 prices, five-PDF upload limit and corporate-use exclusion.
• Mendeley homepage: no named owner or country on the page.