Calibre Comic Conversion Settings Explained
Calibre's comic options are powerful and badly signposted. They live in the Comic Input section of the conversion dialog, they interact with a separate output profile setting that quietly controls image size, and several of the most important ones are phrased as negatives, so the flag turns a default behaviour OFF rather than a feature on. This page lists what each one actually does.
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One thing to clear up first, because a lot of pages get it wrong: Calibre does process comic pages. Out of the box it converts to greyscale, normalizes contrast, sharpens, trims borders and splits double-page spreads, and it has a dedicated right-to-left option for manga. The settings below are how you steer that, not how you bolt it on.
Descriptions here are quoted from Calibre's own ebook-convert documentation. If you would rather not learn any of it, the converter on this page does the same category of work with named device profiles and a live preview instead of flags.
- Files auto-delete after 24 hours
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- The genuine open-source KCC engine
The order to set them in
Set the output profile before anything else
This is the setting people miss. Calibre states that "the output profile also controls the screen size. This will cause, for example, images to be auto-resized to fit the screen." It lives in Preferences, not in the comic options, and everything else is tuned relative to it. For a modern reader with no exact match, Calibre suggests the Generic e-ink HD profile.
Set reading direction
Enable right-to-left for manga. It changes how split spreads are ordered, so setting it after you have already converted does nothing to the existing file.
Decide what NOT to do to the pages
Most remaining options are opt-outs: keep colour, skip the contrast pass, skip sharpening, keep spreads whole, keep borders. Work down the table below and turn off only what you actually want kept.
Convert one chapter as a test
Convert a single chapter, not the whole series, and look at it on the device before batching. Calibre gives you no preview, so a one-chapter test is the cheapest way to find a wrong setting.
Calibre comic input options, and what each one does
| Option | What Calibre says it does | When you want it |
|---|---|---|
| --right2left | "Used for right-to-left publications like manga. Causes landscape pages to be split into portrait pages from right to left." | Any Japanese-order manga. Off by default, so you must set it. |
| --landscape | "Don't split landscape images into two portrait images" | Big screens (Scribe, tablets) where a double-page spread should stay whole. |
| --disable-trim | Disables border trimming. Calibre notes that "for some comics, trimming might remove content as well as borders." | Scans where art runs to the page edge and trimming is eating panels. |
| --dont-grayscale | "Do not convert the image to grayscale (black and white)" | Colour pages on a Colorsoft, a Kobo Colour or a tablet. |
| --dont-normalize | "Disable normalize (improve contrast) color range for pictures." | Art where the contrast pass is crushing greys or flattening screentones. |
| --dont-sharpen | "Disable sharpening." | Already-sharp digital releases where sharpening adds halos. |
| --despeckle | "Enable Despeckle. Reduces speckle noise. May greatly increase processing time." | Noisy scans of old paper. Slow, so use it deliberately. |
| --keep-aspect-ratio | "Maintain picture aspect ratio. Default is to fill the screen." | When filling the screen is distorting pages. |
| --wide | "Keep aspect ratio and scale image using screen height as image width for viewing in landscape mode." | Reading rotated, in landscape, on a small screen. |
| --comic-image-size | "Specify the image size as width x height pixels, for example: 123x321." | Overriding the profile size with an exact panel resolution. |
| --colors | "Reduce the number of colors used in the image. This works only if you choose the PNG output format." | Shrinking file size on flat-colour art, PNG output only. |
| --no-process | "Apply no processing to the image" | Pages you have already prepared elsewhere and want passed through untouched. |
| --no-sort | "Don't sort the files found in the comic alphabetically by name." | Archives whose filenames do not sort into reading order. |
| --dont-add-comic-pages-to-toc | "When converting a CBC do not add links to each page to the TOC." | CBC collections where a per-page table of contents is noise. |
Source of these descriptions
The quoted text comes from Calibre's ebook-convert manual and its Comic Input plugin. We have not benchmarked Calibre's output against ours and make no claim about which looks better; what this page documents is what each option is defined to do.
Calibre is worth keeping
None of this is an argument against Calibre. It is the best free ebook library manager available, its metadata and device-sync features have no equivalent here, and its plugin ecosystem is deep. Converting somewhere else and filing the result in Calibre is a completely reasonable workflow.
Related reading
For a walkthrough rather than a reference, see the guide to converting manga with Calibre. For the case for a focused converter, see the Calibre alternative for manga page.
Frequently asked questions
Which setting fixes manga reading backwards?
The right-to-left option (--right2left). It is off by default. It affects the order that split landscape pages come out in, so it has to be set before conversion; there is no fixing it afterwards short of reconverting.
Why are my pages black and white when the manga has colour pages?
Greyscale is Calibre's default for comic input. Pass --dont-grayscale (or untick the greyscale option in the dialog) to keep colour. Worth doing on a Kindle Colorsoft or Kobo Colour, less useful on a greyscale panel.
What controls the page size?
The output profile, not the comic options. Calibre resizes images to fit the profile's screen, so picking your actual device there is the single highest-impact setting. --comic-image-size overrides it with explicit pixel dimensions if you know exactly what you want.
Is there a preview in Calibre?
Not for the converted comic pages. You convert, transfer, and look at the result on the device. That loop is why this page recommends testing one chapter first, and it is the main thing a browser converter with a live preview changes about the workflow.
Do I need to learn any of this to use MangaConverter?
No. This converter asks for your device by name and applies the matching settings, then shows you the converted pages before you download. The flag table above exists because people search for it and deserve a straight answer, not because you need it here.
This converter runs the genuine open-source Kindle Comic Converter (KCC) engine in the cloud, with device profiles and a live page preview layered on top. We name the engine openly.
KCC on GitHubPick your device by name and see the pages before you download