Focus Plus
The extension is free. Your library, everywhere, is Plus.
One subscription. End-to-end encrypted sync across your devices, your documents preserved against the vanishing web, and a private research dashboard. Cancel any time — your local library never depends on it.
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Arcaneum Focus
The complete focused reader — no account required, nothing leaves your device.
- Full reader mode for articles, PDFs and EPUBs
- Highlights, floating notes, connections, ink, pins
- Focus timer, reading queue, citations
- Everything stored locally on your own device
- No account, no tracking, no upsells in the reader
Focus Plus
or $44.99/year — save 25%
Everything in Focus, kept safe in your own encrypted cloud vault, on every device you read with.
- Encrypted library, every deviceYour highlights, notes and reading positions follow you — pick up a paper on your laptop exactly where you left it on your desktop. Everything is end-to-end encrypted: your passphrase decrypts your data, and nothing else can.
- Documents that stay yoursArticles, PDFs and EPUBs you read are preserved in your private cloud vault. If a page changes, goes behind a paywall, or disappears — your copy and your annotations on it remain.
- The research dashboardA private dashboard at focus.thearcaneum.org/library: every document you've read as a tile, every highlight and note in one searchable place, and projects that gather documents around a question or a chapter.
- Generous room to work5 GB of encrypted storage to start — room for thousands of documents and years of annotations. You can export or delete everything at any time.
Focus for Institutions
Deploying Focus across your organisation?
Universities, schools, libraries, labs and companies can license Arcaneum Focus for managed deployment — the same software, the same local-first privacy, with volume licensing and support built for institutions.
licensing@thearcaneum.org
Cancel any time — sync stops at the end of your billing period, everything you've read stays on your devices untouched, and your encrypted cloud copies are kept for 30 days in case you return, then permanently deleted. Prices in USD. Free accounts can sign in, but only Plus unlocks the cloud.
What we can and cannot see
We store your library. We cannot read it.
Encrypted on your device
Before anything is uploaded, it is encrypted with keys derived from your passphrase — 600,000 rounds of key derivation, on your machine.
We hold only ciphertext
Our servers store encrypted containers and counts. Not a single highlight, note or sentence is ever readable to us.
You hold the only key
No reset, no backdoor. If you lose your passphrase and recovery key, the cloud copy is unrecoverable — your local library is unaffected.