Calibre
E-book library manager that converts formats and syncs to your e-reader.
Quick facts
- Price model
- Open source
- Starting price
- Free
- Best for
- E-reader owners · Format conversion · Personal ebook libraries
- Replaces
- Kindle Unlimited dependency, Paid ebook managers
- Platforms
- MacWindowsLinux
- Last verified
- 2026-06-22
Why it's listed
Own your reading collection as files you can back up, convert, and move between devices.
Calibre catalogs EPUBs, MOBIs, and PDFs, converts between formats, strips DRM from legally purchased books where permitted, and sends titles to Kindle or Kobo. Your library stays on your computer—not a rental platform.
The catch
UI feels dated; Amazon ecosystem integration requires workarounds.
Good fit for
- Kobo and EPUB readers
- Library ebook borrowers who archive
Not ideal for
- Casual readers happy in the Kindle app only
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