useCalibre
For Calibre users · Free

Your Calibre library,
in any browser, Kobo or phone.

useCalibre reads the Calibre library you already keep in your own cloud storage and lets you browse, search, read and download every book from anywhere, with your PC switched off. No server to run, nothing to install, and your books never leave your storage.

Create a free account See how it works

Works with Amazon S3, Cloudflare R2 and any S3-compatible storage. Calibre desktop stays your editor.

useCalibre showing a Calibre library: a grid of book covers with titles, authors, series and reading progress, plus search and filters.

Three old Calibre problems, solved

Calibre on your Kobo, no NAS

KOReader, PocketBook, Moon+ Reader and other OPDS apps browse your whole library and download books straight to the device. No computer left running at home. How to set it up.

Your library in any browser, PC off

The Calibre content server only works while your computer is on. useCalibre keeps your catalog online, so search, covers and reading work from any browser, any time. Read more.

No more cloud-sync corruption

Keeping a Calibre library in Dropbox or Google Drive is the classic way to corrupt metadata.db. Keep it on your PC, copy it one way to a bucket, and read it everywhere. The safe setup.

How it works

Three steps, about ten minutes, and nothing to install on your computer except the copy tool you may already use.

  1. Put your library in a bucket

    Copy your Calibre library folder to Amazon S3, Cloudflare R2 or any S3-compatible storage, for example with rclone sync after closing Calibre.

  2. Connect it with a read-only key

    Give useCalibre the bucket, the folder and a key that can only read. It imports metadata.db and checks for damage first.

  3. Read anywhere

    Browse and read in any browser, download to your Kobo or phone over OPDS, keep books offline. Changes in Calibre appear within minutes.

A reader made for reading

  • EPUB, MOBI, AZW3, FB2, CBZ and PDF, plus TXT, RTF, DOCX and CBR
  • White, sepia, gray and night pages; your choice of font, size, spacing and width
  • Remembers your place on every device; shows chapter and pages left
  • Keep books offline for flights, and install it on your phone’s Home Screen
  • Send a book to Apple Books on iPhone and iPad
All features →
The useCalibre reader on a sepia page, showing a chapter with page controls and reading progress.

Your books stay yours

In your storage, not ours

We keep a catalog and small cover pictures. The books themselves stay in your bucket, and downloads go straight from it to you.

Read-only by default

useCalibre never writes to a library Calibre manages. If you choose to let it manage one, it backs up first and keeps deleted books for 30 days.

Calibre can always take it back

Every book keeps Calibre’s own metadata.opf, so Calibre’s Restore database can rebuild the library at any time.

Private, no tracking

No ads, no tracking cookies, and we don’t sell data. Storage keys are encrypted. Privacy policy.

Built for real libraries

Several libraries, one view

Connect more than one Calibre library. A book in two of them shows once, with each copy on its page.

Share with family

Add people as viewers or editors. Everyone keeps their own reading progress.

Add books without Calibre

Optional: upload straight from the browser to your own bucket, edit details and covers, in Calibre’s own folder layout.

Free. Supported by readers.

You host your own books, so useCalibre costs little to run, and it is free to use, with fair limits. If it makes your reading life better, you can chip in to keep it going.

Create a free account Questions? Read the FAQ