Calibre 9.10

Calibre delivers an all-in-one e-book library tool with robust conversion, syncing, news fetching, and a versatile integrated viewer.

Razvan Serea News Reporter Neowin · Jun 26, 2026 00:14 EDT with 0 comments

Calibre

Calibre is an open source e-book library management application that enables you to manage your e-book collection, convert e-books between different formats, synchronize with popular e-book reader devices, and read your e-books with the included viewer.

It acts as an e-library and also allows for format conversion, news feeds to e-book conversion, as well as e-book reader sync features and an integrated e-book viewer.

Calibre's features include: library management; format conversion (all major ebook formats); syncing to e-book reader devices; fetching news from the Web and converting it into ebook form; viewing many different e-book formats, giving you access to your book collection over the internet using just a browser.

Calibre 9.10 changelog:

New features

Content server: A new "modern" interface with a sidebar to ease navigation
Content server: When used with HTTPS allow installation as a PWA (Progressive Web App)
Edit book: Saved searches: When filtering the list of saved searches match by keywords
CSS parsing: Add support for CSS Level 4 selectors
Cover grid: When using an image larger than the viewport as a texture scale it to fit the viewport
Annotations browser: Allow restricting displayed annotations by custom annotation styles as well
Edit book: Compress images: Add option to convert PNG images to JPEG or WEBP

Bug fixes

E-book viewer: Fix IME on Windows not working when typing in notes for highlights
Conversion: Heuristics: Improve performance in some pathological cases
SNB Input: Fix error on some input files
Windows: fix rare crash when too many notifications are displayed at once
Fix duplicating of books not duplicating value from enumerated columns when the column has a default value defined
Fix a regression in 9.8 that caused errors from AI plugin providers to be silently swallowed and not displayed to user
Fix CSV export invalid when exporting comments field
Disallow Python templates when reading book metadata (CVE-2026-53511)

Improved news sources