One thing to make clear
Mktero is an open-source extension running inside desktop Zotero. The default conversion uses a Mktero account. This website does not collect usage analytics because you visit it. The sections below describe processing that happens when you actively use Mktero to work with papers in Zotero.
With the default converter, a cache miss sends the complete PDF to the Mktero service for your account. No MinerU or Mistral key is required. If you switch to your own MinerU cloud, local MinerU, or Mistral, the PDF goes there instead and is not sent to Mktero. Read the relevant privacy terms before processing sensitive papers.
The data map
The table separates where each data type is sent or stored from whether Zotero syncs it. Mktero does not sync local data to other devices itself.
| Data | Sent to or stored in | Zotero sync |
|---|---|---|
| Complete PDF on a cache miss, with the default Mktero converter | The Mktero service for the signed-in account | Not by Mktero |
| Complete PDF on a cache miss, after you switch to your own converter | Selected MinerU cloud, the configured local MinerU service, or Mistral | Not by Mktero |
| MinerU cloud token, local MinerU address, Mistral API key, and AI credentials | Active Zotero profile, unencrypted | No |
| Email and password when signing in or registering, and the registration verification code | The Mktero service you select; the password and code are not saved | Not by Mktero |
| Mktero access token and refresh token | Active Zotero profile, unencrypted | No |
| Account profile and conversion-activity counts, requested with the access token while the account pane is open | The Mktero service you select | Not by Mktero |
| Mktero extension version, sent with requests to the Mktero service and recorded when you sign in or refresh your token, so the operator can see which builds are still in use | The Mktero service you select; operations reporting only, never returned to the extension or shown in your profile | Not by Mktero |
| Research invitation email, the token link, the answers you submit, and the research-email opt-out | The Mktero service you select; the link token is not saved on this site | Not by Mktero |
| Cached Markdown, figures, source maps, PDF indexes, corrections, and translations | Active Zotero profile, unencrypted | No |
| Focused DOI/arXiv/OpenAlex identifiers and provider-specific candidate identifiers | Semantic Scholar, OpenCitations, or OpenAlex | Not by Mktero |
| Bounded citation text after you choose Import reference for a title-only reference | OpenAlex | Not by Mktero |
| A normalized DOI, arXiv ID, PMID, or OpenAlex work ID plus confirmed metadata after import, with an optional public PDF request | Selected metadata/PDF provider | Not by Mktero |
| Protected Markdown translation batches | AI provider configured by you | Not by Mktero |
| Selected Markdown text and bounded surrounding source context for selection translation | AI provider configured by you | Not by Mktero |
| Zotero PDF annotations | Local Zotero library | According to Zotero settings |
| Saved snapshot Note and attachments | Zotero items and attachments | According to Zotero settings |
| Exported Markdown and figures | User-selected local path, including an Obsidian vault. Mktero does not sync that copy | No |
| Obsidian export index: library ID, item key, note folder, content hash, and vault path | Active Zotero profile, unencrypted | No |
| Imported reference metadata and PDF attachments | Active Zotero profile, unencrypted | According to Zotero settings |
What is not sent to reference or PDF providers
Reference lookup and import are local-first and explicitly triggered. Providers receive only the bounded data required for the current action.
- PDF annotations, local PDF.js indexes, and Zotero notes
- Complete Zotero item records and local file paths
- Cached Markdown, PDF bytes, and Zotero keys
- API tokens, presigned URLs, and authenticated responses
What you control
Choose where the PDF goes
The default is your Mktero account. A cache miss sends the complete PDF to the Mktero service, and no MinerU or Mistral key is required. Choose your own MinerU cloud, local MinerU, or Mistral if you do not want that PDF sent to Mktero, and review that service's terms first.
AI is opt-in
Full-article and selection translation only send data to the AI provider you configure after you enable the feature.
Explicit reference import
Bounded citation text, normalized identifiers, or confirmed metadata are sent only after you click an import action.
Local storage
Caches, credentials, and reading data stay unencrypted in the active Zotero profile and are not synced by Mktero.
Research invitations
Mktero occasionally emails a short research survey to the address on your account. This is not a verification code or a password reset. Turning it off does not affect conversion or those messages.
An invitation that only points here can be stopped after you sign in. On your account page, turn research invitations off. You can turn them back on there.
Invitations sent after this control was added also contain a direct opt-out link. That link only turns invitations off. It does not show your email, and it cannot turn them back on.
Answers you already submitted stay with that invitation. Turning invitations off does not delete your account.
Third parties and responsibility
On the default path, the Mktero service receives the complete PDF. MinerU, Mistral, AI providers, Semantic Scholar, OpenCitations, OpenAlex, and metadata or public-PDF providers each have their own privacy policies and retention rules, and they receive data only when you select them. Mktero controls the scope of data it sends, but cannot change how those services process it.
Read the privacy terms for the Mktero service and for every provider you select. Do not process confidential PDFs unless those data-handling terms suit your use case.