SOFTWARE LICENSE GUIDE
Calibre
Calibre is a powerful, free, and open-source e-book management software.
What it does
It allows users to organize, manage, convert, and read e-books across various formats and devices.
Who it may suit
E-book readers and collectors who need to manage, convert, and organize their digital library.
Free tier and license
N/A (Fully free and open-source)
Limitations to check
N/A (Fully free and open-source)
Licensing notes
Licensed under the GNU General Public License v3 (GPLv3), allowing free use for personal and commercial purposes.
Verification details
Last licensing verification recorded: 2026-10-28.
Directory record last updated: 2026-08-23. These are separate dates: a record update does not necessarily mean the publisher's terms changed.
AI-assisted summaries may be incomplete or outdated. Confirm licensing, pricing, and commercial-use rights in the official sources before making a business decision.
Frequently asked questions
Is Calibre free?
Yes, Calibre is free and open-source software licensed under the GPLv3.
What can I do with Calibre?
You can use Calibre to organize your e-book library, convert between e-book formats, edit metadata, and sync books to your e-reader.
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