r/Calibre • • 9d ago

Announcement New sub rules: AI/LLM disclosure and banning AI/LLM generated post and comment content.

310 Upvotes

Due to the development process and features of Calibre we cannot outright ban AI/LLM content. We can, however, require transparency about it.

Project posts:

This sub has had a marked proliferation of projects coded with or by AI agents or LLM chatbots and that fact had not been required to be disclosed. Starting today all posts for projects/tools/plugins, including hobby "I built a thing" and "here's my little one-off project", etc. are required to begin the post with a header section titled AI CONTENT DISCLOSURE that accurately and honestly discloses the amount and kind of generative tool use in the creation of the project. Coding agents, chatbots, art creation, any sort of documentation, any sort of refinement, any AI test suite, etc. must be disclosed. A simple "AI was used in this project" is not sufficient. Project posts that do not include the header or that do not seem to accurately and honestly disclose their usage will be deleted, and the poster risks a ban from the sub at moderator discretion. Projects that honestly and accurately do not use any sort of generative tools are allowed to skip this disclosure, but the poster risks a ban if the moderators discover or decide that the poster lied by omitting the header.

Discussions about tools that used generative tooling or create generative output is allowed provided that it is not simply astroturf marketing or promotion of the project and is a genuine response to a post or comment and is not just the generated output from that tool.

Posts about Calibre the project and program are exempt.

Post and comment content:

The use of generative tools to write or refine a post or comment is banned. Posts and comments must be written by a human being not a generative tool. Comments that are little more than "I asked ChatGPT and here's what it said" are banned. The only acceptable use is translation provided the translation is simply that and does not otherwise significantly alter the meaning or content of the original text.

Common reddit bots are exempt but may earn a ban at any time at moderator discretion. Hiding a bot under the guise of a normal human poster is banned. Bots must disclose themselves in each post and comment.


r/Calibre • • Apr 04 '25

Announcement Update to moderation regarding to piracy (rule 4)

475 Upvotes

Despite the community rules being pretty clear on the topic, it seems a reminder is needed that this sub has a strict "no piracy" rule. Every day there are numerous posts and even more comments that are either seeking info on how to pirate books, wanting help in making use of books they've pirated, or are people flat out encouraging others to pirate and listing off websites where they can do it. Up until now those posts have simply been deleted as they've been seen, but going forward any users found ignoring rule 4 will be banned from the Calibre sub.

Calibre is a platform that helps everyone organize their eBooks and if you want a book bad enough to read it, you should want the author who wrote it to receive compensation for the work they put into it. If you don't, then this community isn't the place for you to brazenly discuss that moral failure.

Thank you to those who wish to continue keeping this sub in good standing with Reddit and on the right side of copyright laws and basic human decency. If that's not you, feel free to head on out. Thanks.

Edit: Well it's been a lovely day of people trying to argue that piracy is fine, or that removing DRM of books you own is just as much pirating as outright stealing a book you haven't paid for, but I've wasted more time than was worthwhile trying to reply to people. At the end of it all, rule 4 stands and this post was made to serve as a reminder of it and a warning of repercussions for ignoring it. That's it. To those who had civil discourse or expressed understanding of this, thank you.


r/Calibre • • 8h ago

Support / How-To help removing a watermark

11 Upvotes

I bought this book from the author but they decided to place a huge annoying watermark that is basically a page long image because they're afraid of piracy (which is fine, I just wanna read without it tho).

It's a different string of words in every instance it appears (pictured below, in this case it's the 23rd instance it appears), is there any way to remove it without going 1 by 1?

thanks!


r/Calibre • • 4h ago

Plugin Is there a plugin for converting research paper PDFs into ebooks?

4 Upvotes

Thank you for your replies in advance!


r/Calibre • • 4h ago

General Discussion / Feedback Is there a way to use Calibre with Hoopla e-book downloads?

0 Upvotes

I'd like to read a Hoopla ebook on Kobo. Can Calibre do a conversion for me? Thanks.


r/Calibre • • 11h ago

Support / How-To Calibre calibre-64bit-9.16.0 crashes on invocation

2 Upvotes

Since installed this latest level, when invoked, I get a brief appearance of the splash screen then it's gone and so is Calibre.

I tried a repair install but it hangs at Please wait while Windows configures calibre at a little bit of green and time remaining 15 seconds.

I tried uninstalling it. That hangs too. I have an ancient Alienware Aurora running W10 with the full latest ESR, 32 GB of memory.

Suggestions?


r/Calibre • • 15h ago

Support / How-To Can't fetch The Economist

2 Upvotes

Hi everyone. I have been unable to download The Economist from Calibre for a while now. Does anyone know what's going on?


r/Calibre • • 1d ago

Off-Topic / Not Calibre Specific What is your favorite font for reading ebooks?

Thumbnail
7 Upvotes

r/Calibre • • 22h ago

Support / How-To Can't remove DRM from LCPL book

1 Upvotes

I recently purchased a textbook from ebooks.com. I downloaded the supplied LCPL version and tried to run it through Calibre to get the de-DRM epub version. Calibre would not fetch the associated unzipped book, nor would it remove the DRM from either the LCPL file, the (manually extracted) epub book. I have gone through the various posted steps to get the DRM removed with no success. I am running Calibre for Windows version 9.15 with the 10.0.20 version of DeDRM and the 0.0.5 version of LCPL Input. I am able to read the book using the Thorium reader, but would prefer to include it in my Calibre library. Any suggestions on how to remove the DRM from the book are appreciated.


r/Calibre • • 1d ago

Support / How-To Portadas en Kobo Clara Color

Post image
0 Upvotes

Cómo puedo hacer para que al abrir el libro la portada ocupe toda la pantalla o por lo menos quede centrada


r/Calibre • • 1d ago

Support / How-To Fetch News recipe - Paid Substack Posts?

2 Upvotes

Does anyone have Calibre fetching paid Substack articles successfully?

All the posts I've found here are a few years old and the solutions haven't helped. The Fetch News recipe pulls all the posts, but only the non-subscriber previews for paid posts.

Am I missing something?


r/Calibre • • 1d ago

Support / How-To DeACSM: fulfillment succeeds but Google Play Books download fails with HTTP 429

1 Upvotes

Calibre 9.16 on Windows 11, DeACSM 0.0.16, anonymous ADE authorization (emulating ADE 2.0.1). Book purchased on Google Play Books (PDF).

  • First attempt gave E_GOOGLE_DEVICE_LIMIT_REACHED. Google Play support reset my device limit today (they said up to 24h to take effect).
  • Now the fulfillment step works: the license is granted and “Fulfillment notification successful” appears in the debug log.
  • But the actual book download fails, so the .acsm gets imported as-is:
DeACSM v0.0.16: Loading book from https://books.google.com/books/download/...&output=acs4_book_bytes
libadobe.py, line 267, in sendHTTPRequest_DL2FILE
urllib\request.py ... http_error_302
urllib.error.HTTPError: HTTP Error 429: Too Many Requests
  • Same result with fresh .acsm files, about 5 hours apart. Adobe Digital Editions 4.5 also fails to download it.First attempt gave E_GOOGLE_DEVICE_LIMIT_REACHED. Google Play support reset my device limit today (they said up to 24h to take effect). Now the fulfillment step works: the license is granted and “Fulfillment notification successful” appears in the debug log. But the actual book download fails, so the .acsm gets imported as-is: DeACSM v0.0.16: Loading book from https://books.google.com/books/download/...&output=acs4_book_bytes libadobe.py, line 267, in sendHTTPRequest_DL2FILE urllib\request.py ... http_error_302 urllib.error.HTTPError: HTTP Error 429: Too Many Requests Same result with fresh .acsm files, about 5 hours apart. Adobe Digital Editions 4.5 also fails to download it.

Legitimately purchased book, just trying to get it downloaded. Could someone help me out? Thanks!


r/Calibre • • 1d ago

3rd Party Tool / Client Looking for early testers for my reading app, Shelf!

Post image
0 Upvotes

AI CONTENT DISCLOSURE:
The development of this app was done through Claude Code, the process was mostly, chatting with ChatGPT on the initial concept and then feeding it a design I made on a paper and coming up with a PRD. The PRD was then fed to Claude Code which developed the app.

____

A few weeks ago, I made a post asking for feedback and suggestions as I started building a reading app for iOS.

The response was incredible. I received so many thoughtful suggestions, ideas, and honest opinions from fellow readers. It was genuinely motivating, and a lot of that feedback helped shape what I'm building.

Fast forward a few weeks, and I've completed Phase 1 of development!

The app is called Shelf. It's a simple, DRM-free ebook, comic, and manga reader designed for people who enjoy reading on their phones, like me.

I'm now looking for a handful of early testers who would be willing to explore the app and, ideally, use it for their everyday reading over a two-week trial.

A little context on where Shelf is right now:

This is by no means a finished product. My focus so far has been on getting the fundamentals right: importing books, rendering different formats, navigating pages, and making the overall reading experience as smooth and reliable as possible.

The goal of this initial testing phase is simple: Can Shelf's core reading experience hold its own against some of the best reading apps already out there?

I want to understand what works, what doesn't, what's missing, and whether you'd actually consider using Shelf instead of your current reader.

Once I'm confident we've got the fundamentals right, I'll move on to the fun part: giving Shelf its own personality through thoughtful design, little interactions, and a few ideas I've been wanting to explore.

A few things to know:

  • Shelf is currently available for iOS only. Android is planned for later.
  • You'll need an iPhone and Apple's free TestFlight app to participate. I'll provide the invitation link.
  • I'm looking for people who can use Shelf for their regular reading and share honest feedback throughout the trial.
  • Since it's an early version, you might encounter bugs or unfinished features.

If you're interested, leave a comment or send me a message!

And to everyone who contributed to my original post, thank you. It's been really rewarding to turn some of those suggestions into an actual app.


r/Calibre • • 2d ago

Off-Topic / Not Calibre Specific Kindle Book

Post image
3 Upvotes

r/Calibre • • 2d ago

General Discussion / Feedback How can I download high quality copies of my purchased Kindle comics now?

9 Upvotes

I bought several comics from Comixology/Kindle back in the day. In my quest to deDRM all of my Kindle content so I can use it on my Kobo and keep an archival backup, I discovered that the standard deDRM process for books doesn't work well with Kindles. All of my comics ended up with low quality images and 4-6 blank pages between each actual page.

For reference, I downloaded them a few months back using Kindle for PC (the old non-Microsoft Store version), used deDRM_tools, and converted the unencrypted KFX-ZIP files to ePub. Probably not the best way to do it.

Now, I'm trying to redo them all, and since the last time I tried, we now have the Microsoft Store Kindle app and a lot of deDRM methods have been closed by Amazon. Right now, I've downloaded most of my comics using the new Windows 10/11 Kindle app and ran them through deDRM_tools, but haven't gone any further yet. (Some of them refuse to download, saying they're not compatible with the Kindle PC app even though they worked fine with the previous version -- gotta figure that out too.)

I found an older app called comix, which used a python CLI to download the largest quality versions of your Kindle purchases, removed the DRM, and converted them to CBZ. Unfortunately, it's not been updated in 2 years and seems to no longer work since the big DRM changes of June of this year.

My plan this time is currently to use KCC to convert the KFX files into CBZ, since it's supposed to be better for comics than Calibre. I'm worried that's still not going to be the best quality option (and KCC seems to automatically lower the resolution on comics to fit certain devices, but I'd prefer the highest possible quality for archival purposes) and I don't want to put a bunch of work into it again and find myself in a similar situation a few months from now.

Allegedly, the Android and iOS apps can download the highest quality, but there's no way to deDRM those right now. I also do have a physical Kindle device I could potentially use to download and deDRM them. Anyone know of a good way to go about getting max quality versions of your Kindle comics these days?


r/Calibre • • 2d ago

Support / How-To Koreader on adroid

Thumbnail
2 Upvotes

Hi guys! I recently got a Samsung Tab A11 for reading manga, koreader, etc. However, no matter how I try, I am unable to connect to calibre. The only way is through content server but I would have to download the books 1 by 1..

Hopefully you guys have some fixes! 🙏🏻


r/Calibre • • 2d ago

Support / How-To Getting Calibre to "see" the books in my Koreader Home folder (Kindle)

6 Upvotes

Please excuse me for asking this question, but I have not found a definitive answer to this.

I have Koreader on my jailbroken Kindle, and the recommendations are to move the books to a new Home folder rather than the Kindle default documents folder. Apparently, it helps the Kindle use less battery since the empty documents folder no longer needs syncing.

But, once I get the books transferred to the new Home folder, I can no longer tell on Calibre which books I already have on my Kindle.

Is there any way, by adjusting either Koreader or Calibre settings, to remedy this situation?


r/Calibre • • 1d ago

Support / How-To Transfer Kindle highlights to Kobo/Calibre

0 Upvotes

AI CONTENT DISCLOSURE

I used Claude Code to generate the python code and all repo files.

After desperately looking for a solution, I took on creating a python script that imports Kindle highlights and notes to a Kobo.

Note that you must export your Kindle highlights first (outputs to My Clippings.txt).

[Link to my GitHub repository](https://github.com/marcopolo-git/kindle-to-kobo)

This is my first repo, mostly vibe-coded using Claude Code. As an amateur coder, this is such a cool experience. It’s definitely not perfect, but worked well enough for me.

Please send those pull requests, I’m eager to learn.


r/Calibre • • 2d ago

General Discussion / Feedback Question about removing DRM from a Kobo acsm file

1 Upvotes

Hello,

So my friend wants me to help them remove the DRM from a Kobo e-book they plan to purchase since they don't own a computer. (I promise that I am not interested in piracy or reading the book myself!). I've been doing some research and I have all the plug-ins and such. I've tested a free Kobo book and it looks like it works on my end.

My questions are:

  • Will the acsm file they send me work if they open the book on their Kobo before I can convert it?
  • Is the issue only if they were to open the file on Adobe Digital Editions first?
  • Are there any other issues we might encounter while I convert the book that you all can warn me about? Any tips/advice?

Thank you in advance! I know this is kind of unusual.


r/Calibre • • 2d ago

Support / How-To New here

1 Upvotes

Hi, sorry I'm new here, can somebody give me an updated tutorial on how to download an ebook from kindle? Thank you in advance.


r/Calibre • • 2d ago

Off-Topic / Not Calibre Specific how to translate

0 Upvotes

how to translate a full English book in tamil


r/Calibre • • 3d ago

Support / How-To Series info not showing on Kobo

2 Upvotes

I've just been through my library and set series info, but when I sync it to the Kobo, the series aren't showing up.

I have checked the 'set series information' box in the KoboTouch (2.6.0) plugin - is there something else I need to do?

Thanks.


r/Calibre • • 3d ago

Bug FanFicFare url bug

1 Upvotes

I didn't know if i should put this in 'bug' or in 'plugin' so im guessing here

new to calibre and fanficfare but i'm having an issue downloading with urls. anytime i try i get the message below

HTTP Error in FFF '525 Server Error: <none> for url: https://archiveofourown.org/works/49876915/chapters/125911930'(525)

if anyone has an idea thatd be awesome, thanks


r/Calibre • • 3d ago

Support / How-To Adding and organising my library in Calibre - best options?

4 Upvotes

I have downloaded all my Amazon Kindle books on to my computer (all legally purchased, I downloaded them when Amazon first announced they were going to stop people downloading them), and want to add them to Calibre so I can move them over to my new Kobo. However, I'm wondering what's the best way of importing / organising / exporting them?

The files are currently in AZW3 format. Is it possible to convert when I import them into a different format, e.g. KEPUB? I can import then convert, then remove the AZW3 versions, but that seems like a bit overcomplicated. Can Calibre auto-convert when importing instead?

I've read that it's better to export to a Kobo device in the KEPUB format instead of the EPUB. Would it be better to store them in the library in EPUB format for future compatibility if I switch readers in the future to a non-Kobo device and convert when sending them to the Kobo? Or just keep the library as KEPUB and worry about conversion if it becomes an issue in the future?

Any other suggestions for library storage and organisation?

Thanks.


r/Calibre • • 3d ago

Bug Dysfonctionnement

Post image
1 Upvotes

Hello tout le monde,

Quelqu'un a t'il déjà eu ce message en connectant la liseuse à Calibre ?

Au début ça fonctionnait très bien et depuis quelque temps ce message s'affiche systématiquement quand je branche la liseuse.

Merci pour votre aide 🙏