Pricing
Your Zotero library in claude.ai, on your phone, and in ChatGPT.
Nothing to install. Add one URL, sign in with Zotero, and ask. Using Claude Desktop, Claude Code or Cursor? The free local install already does everything, and you do not need a plan.
Individual
Most researchers€69/year
or €7/month
14 days free, then €69/year. Cancel anytime.
One researcher, nothing to run.
1 person
- Connect in claude.ai or ChatGPT with one URL
- Personal or permitted group library, for one researcher
- Per-user Zotero login, encrypted at rest
- Always on, maintained and updated
- Email support · cancel anytime
Lab
Most labs€99/month
or €990/year, two months free
Your whole group, on your shared Zotero group library.
Up to 10 seats
- Everything in Individual, for 10 people
- Shared billing for your research team
- A 15-minute setup call with the maintainer
- Priority email support
- Invoicing and purchase orders
Department
€299/month
or €2,990/year
A faculty, library or institute.
Up to 50 seats
- Everything in Lab, for up to 50 people
- Onboarding session for your researchers
- Data Processing Addendum (GDPR Art. 28)
- Procurement paperwork handled
- Named contact for your institution
Works when your PDFs sync to Zotero storage and your Claude or ChatGPT plan allows custom connectors. See the full requirements.
On Claude Desktop, Claude Code or Cursor? Install Zoteus free on your computer.
Secure checkout & EU VAT via Polar · monthly or annual, chosen at checkout · cancel anytime
Before you pay: the full requirements
- Your AI account: Zoteus does not include a Claude or ChatGPT subscription. Confirm custom connector access first. ChatGPT needs Developer mode on a supported paid web plan; workspace administrators may restrict it.
- Your files: hosted access uses Zotero online. Metadata sync is not file sync. Files only on your disk or in WebDAV are not available as hosted PDF bytes.
- Your search coverage: hosted currently searches metadata, notes and PDF full text by keyword; search by meaning runs in the free local install. PDF-body indexing is opt-in in the software, with defaults of 5,000 items and 40,000 body-text characters per item. Ask support to confirm the caps for your library before relying on them.
- Your libraries and data: ordinary calls can use permitted groups, and each library you use, personal or group, can have its own search index, searchable one at a time or together. Hosting is currently in the US. Retrieved text goes to your AI service; check your institution's requirements.
“I’ve enjoyed using Zoteus immensely, largely because I am able to talk to my Zotero library and notes and query things that I would have otherwise been unable to do. It’s made years of research trickling in in bits and pieces become part of a larger whole and I’m extremely grateful to Oscar and the Zoteus team for enabling that.”
For research groups
Try it with your group library for 30 days.
If your team screens references together in a Zotero group library, the setup is the part that costs you an afternoon. So I do it with you: a 15-minute call, your group library connected, and 30 days to decide whether it earns its place. No card, and no obligation at the end of it. How a review team sets up a shared library.
How the hosted plans work
- 01
Subscribe
Check out via Polar and get a license key by email.
- 02
Connect
Add mcp.zoteus.com/mcp as a connector in claude.ai or as a plugin in ChatGPT, and sign in to your own Zotero.
- 03
Verify a passage
Confirm the selected library, find a known paper, and check a retrieved quotation against its PDF page.
Connector URL: https://mcp.zoteus.com/mcp
Questions
Can Individual access a group library?
Individual is for one researcher, including the group libraries their Zotero account permits. Lab pays for up to ten people, assisted setup, priority email support, and invoicing or purchase orders. Group access is not a feature paywall. Neither plan promises multiple persistent library indexes or combined semantic search. Group-library setup and index limits.
Are embeddings and all my PDFs included?
Hosted currently searches metadata, notes and PDF full text by keyword. Search by meaning runs in the free local install. PDF access also depends on Zotero file availability: local-only and WebDAV file bytes cannot be fetched by the hosted connector. Check search readiness.
Why pay if it’s open-source?
You’re paying for hosting and maintenance, not features. Self-hosting gives you the same capabilities for free, forever; the hosted plans mean you don’t have to run or update anything.
Does it work with ChatGPT?
Yes, on the hosted plans or with your own self-hosted remote. ChatGPT only connects to remote MCP servers, so the free local install does not apply to it. You need Developer mode, which OpenAI offers on the paid ChatGPT plans in the web app (Settings, then Security and login); a free ChatGPT account cannot add custom servers. Then add mcp.zoteus.com/mcp as a plugin and sign in with your Zotero account. Step by step: Connect ChatGPT to Zotero.
What counts as a lab?
A research group sharing one Zotero group library: a PI, postdocs, PhD students, and whoever else screens references with you. Up to 10 people on the Lab plan, up to 50 on Department. Arrange member access with support during setup. License keys can be bound to a Zotero account, so do not assume one key can be reused by every member.
Can we try it before we pay?
Yes. Individual starts with 14 days free, and you can cancel anytime from the Polar customer portal. Labs get a free 30-day pilot and I run the setup with you on a call. If it doesn’t fit your workflow, nothing happens at the end of the 30 days.
Is my data safe?
Your Zotero key is encrypted at rest (AES-256-GCM) and only ever used to talk to your own Zotero library. Zoteus is a data processor, not a data owner. You can revoke access at any time, and reads stay scoped to your library. Retrieved passages are sent to your chosen AI service. The software supports optional usage logging, disabled by default, and the hosted service keeps operational logs with secrets redacted for up to 30 days. See the privacy policy for storage and data paths.
Can I cancel?
Yes, any time from the Polar customer portal. Your access continues until the end of the billing period; there’s no lock-in and your library is always yours.
Can you invoice us, or take a purchase order?
Yes, on the Lab and Department plans. Annual billing suits grant funding better, and the annual price is two months cheaper than paying monthly. Email me and I’ll send an invoice.
How does billing work?
Checkout and billing are handled by Polar as the merchant of record, so EU VAT and receipts are taken care of. You’ll receive a license key to paste when you connect.
Prefer to self-host? It’s free, with every feature: start here. Questions? support@zoteus.com