Calibre on the BookBird Author Score
Author Score · book formatting · #8 of 10
Best for: Authors converting a DOCX or EPUB between ebook formats for free
64.3 of 100 points = 6.4 out of 10. How this score is calculated
Author jobs, from Calibre’s own pages
- Yes: EPUB for ebook stores
- Not stated: Print-ready PDF in KDP trim sizes (not stated)
- Not stated: Ready-made book designs (not stated)
- Not stated: Device and print preview (not stated)
- Yes: Imports a Word file
- Yes: Front and back matter
- Not stated: Full-bleed images (not stated)
- Not stated: Several editions from one file (not stated)
Calibre pricing
Free. There is a free plan. The plans as Calibre’s own site listed them on October 7, 2026, in US dollars:
- Calibre: Free (donations accepted)
Free and open source.
What Calibre offers
From Calibre’s own pages, checked on October 7, 2026:
- Converts dozens of formats, DOCX in, EPUB and AZW3 out
- Built-in editor for EPUB and Kindle files
- Generates a table of contents during conversion
- PDF output at standard or custom page sizes, with headers and footers
- E-book viewer for all major formats
- Library manager with metadata download and editing
- Content server to read or share books in a browser
- Plugin explorer with hundreds of plugins
Runs on: Windows, Mac and Linux. Exports: AZW3, EPUB, DOCX, FB2, HTMLZ, KEPUB, MOBI, PDF, RTF, TXT and ZIP. Launched: 2006.
Who Calibre suits, and what its pages do not say
Best for: Authors converting a DOCX or EPUB between ebook formats for free.
Not confirmed on Calibre’s pages when we checked: print-ready PDF in KDP trim sizes, ready-made book designs, device and print preview, full-bleed images and several editions from one file. That is what the vendor states, not a test; a feature can exist without being described, and the score only credits what is.
About 3,600 people a month search Google in the US for “calibre ebook”, up 33% over the past year (Google Ads data via DataForSEO).
Calibre alternatives
| Software | Score | Price from | Best for |
|---|---|---|---|
| Draft2Digital | 9.0 | Free plan | Authors wanting free EPUB and paperback PDF, publishing wide or not |
| Kindle Create | 8.6 | Free | KDP authors wanting free, simple formatting for text-heavy books |
| Atticus | 7.8 | $147 one-time | Self-publishers who write and format in one app, any OS |
| Vellum | 7.1 | $199.99 one-time | Mac-based authors formatting many books for a one-time price |
| Reedsy Studio | 6.9 | Free plan; paid from $52.99 a year (add-on) | Authors wanting free typesetting and real-time editor collaboration |
Compare: All book formatting · All software for authors
Calibre questions
How much does Calibre cost?
Free.
What does Calibre run on?
Windows, Mac and Linux, according to its own site.
What file formats can Calibre export?
AZW3, EPUB, DOCX, FB2, HTMLZ, KEPUB, MOBI, PDF, RTF, TXT and ZIP, according to its own site.
How the score is computed: the formula, step by step. Prices and features were read from Calibre’s own site on October 7, 2026; nobody pays to be listed.