Submitted by sudo moderator in freeAsInFreedom

Last week's thread (non-onion link).

This week's Free Software Application of the Week is calibre, a free ebook reader. Ohhh boy, this one is a good one.

Calibre can read all the commonly used ebook formats, as well as some of the less commonly used ones (not PDF, though, but it will open PDFs using whatever PDF viewer you have installed). When you import an ebook into calibre, it will copy it to calibre's working directory (so you are free to delete the original file afterwards), and will display it in the list of books. Each book in the list has tags associated with it, which you can use to narrow down the list. For example, you could ask calibre to only show you fiction books, or books written by one particular author. I don't have enough books in my library to make use of this feature, but I see how it could be useful for very large libraries.

On the bottom of the main viewer, there are a few buttons that change the display. One enables a "cover browser" feature, which shows the cover of each book at the top of the screen, displayed in a "jukebox" fashion, like this. There is also the cover grid feature, which replaces the list of books with a grid showing only the covers. I prefer this format.

Another interesting feature is the ability to edit a book's metadata. Calibre stores some metadata for every book. These data are things like the title, author, ISBN, publishing date, blurb, cover art, and a few others. You can manually edit this if you want, but I almost never do, because calibre has a really great feature that lets you download the metadata for a particular book from Google or Amazon (just make sure the title and author are correct, first). This saves me a lot of time. My favourite part is it lets you change the cover of the book. If it comes with a version of the cover you don't like, or no cover at all, it'll search Google and Amazon for covers for that particular book, and let you choose the one you like best. Alternatively, if you don't like any of them, you can generate your own generic cover (see the covers for "The State and Revolution" and "What is to Be Done?" in this screenshot).

When you double-click on a book, calibre opens the ebook viewer. This is a pretty simple window that displays the text of the book. By default, the text is shown in page mode, where the text is broken up into virtual "pages." Spacebar turns to the text page, with a fancy page-turning animation. Page down does the same thing, and page up turns back a page. If you prefer to switch pages without a page-turning animation, use the left and right arrow keys. There is also flow mode, where it displays all the text on one page, and you have to scroll down the page to read more, like in a web browser. I prefer the page mode.

There are a few buttons on the left side of the viewer, which I never really use. They let you do things like increase or decrease the font size, put in a bookmark (calibre remembers what page you were on when you close the viewer, so this is just there for when you need to come back to one part of the text later), a reference mode, which shows you a unique number for the paragraph you mouse over (useful when referring to a specific paragraph in the book), and a few other things. To me, the most useful feature of the reader mode is the search bar, which lets you search for instances of a certain word or words in the text.

Another great feature calibre has is the ability to edit epub and azw3 ebooks. The editor allows you to edit the actual HTML for the book. This lets you make some powerful edits, but it is a bit complicated if all you want to do is make a small edit, like correcting a typo. I'd really like it if calibre let you edit the text from the viewer, because that would let me correct typos or OCR errors as I'm reading. As it is, it's too cumbersome to open the editor, find the html page for the chapter I'm on, find the exact sentence, correct the typo, save the changes, and do the entire thing over again when I find another typo. If I could quickly switch to an edit mode within the viewer, that let me edit the rich text (like in LibreOffice Writer), then save the changes and go back to reading, I could correct typos easily, but it's just too much work for right now, unless you want to read the entire book from the editor (don't).

The last major feature of calibre is the ability to convert ebooks from one format to another. There is no need to do this if you only use calibre for reading, but it can be useful if you want to send a copy to a friend, but their ebook reader needs a different format of ebook. If you connect a physical ebook reader to your computer (like the Kindle), calibre will let you send ebooks to the device, automatically converting them if they're not the right format. I don't own a physical ebook reader, so I can't testify to the effectiveness of this, but I assume it works.

So, calibre is a really well-made program. It's the best ebook reader that I've come across, and I highly recommend it to anyone looking for an ebook reader. Once you've got it, the only thing missing are some ebooks to read. For that, I recommend checking out this list (non-onion link) of free online libraries. Also, subscribe to /f/books if you enjoy reading - I'm planning on writing reviews of some of my favourite books over there.

And that's it for this week's Free Software Application of the Week. What should I review next week? Let me know in the voting thread (non-onion link). Thanks for reading, and I'll see you all next Monday!



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ziq wrote

This is one of the top 3 foss programs that prove foss is best.


zombie_berkman wrote

Calibre is cool. I use to use it to strip drm from etextbooks in college


sudo OP wrote

Didn't know it could do that - neat.


jaidedctrl wrote

Related: My Calibre library is available at, thanks to Calibre's built-in content server. Calibre is fantastic!


sudo OP wrote

Yes, I forgot to mention that! So useful.


josefStallman wrote

Brilliant as always, comrade. Thank you for linking the list of ebooks, I've been looking for some stuff to read.


Mullvaden wrote (edited )

I've actually only used it to make epub's with from html-files, so that is the biggest feature for me.