# ebook-fonts: typefaces patched for E Ink screens

> The ebook-fonts repository is a curated collection of fonts altered for e-readers, with family names changed, metrics adjusted, glyphs redrawn and hinting modified so text renders well on E Ink. It suits a Kobo, Kindle or Boox reader who wants better typography, and it is a font collection rather than a reader.

**nicoverbruggen/ebook-fonts** — Selection of fonts with modified line height and family names, optimized for e-reading, particularly for Kobo, Kindle and Boox devices.

- Repository: https://github.com/nicoverbruggen/ebook-fonts
- Website: https://nicoverbruggen.be/fonts
- Stars: 1,021 · Forks: 14
- Language: Python
- License: not declared
- Published: 2026-10-20 · Updated: 2026-10-20 · Language: en
- Canonical page: https://hysenlabs.com/projects/nicoverbruggen-ebook-fonts

## What kind of alteration each font got

The repository is a collection of fonts altered in some minor way for better compatibility with e-readers, in particular Kobo devices, and the README is specific about the kinds of change involved.

For some fonts the family names have been altered. Sometimes glyphs have been altered. Sometimes metrics have been altered. Sometimes hinting has been modified. All of it is in service of readability on E Ink displays.

Those four categories are worth separating, because they have different consequences.

A name change is a workaround rather than a design decision. The README gives the reason for Sourcerer, which is a thicker version of Source Serif 4 with 20 percent spacing: it has been renamed so it works correctly on Kobo devices, because fonts containing a number will not work due to a bug in Nickel. So the name is not cosmetic, it is a workaround for a firmware bug in the reading stack.

A metric change is the substantive one for reading. Line height and spacing determine how much vertical space a line of text occupies, and on a low resolution greyscale display that is the difference between comfortable and fatiguing.

A glyph change is a design decision by the author, and the Core Collection entry for Libron is an example: a modified version of Readerly with manual edits for a more neutral look, where the serifs have been trimmed down on several capitals, certain glyphs have been reworked, and composite glyphs have been fixed, producing a more subtle serif that is less in your way.

A hinting change is the deepest one, because hinting is the instruction the font gives to the rasteriser about how to fit a curve to the pixel grid at a given size, and that is exactly what E Ink's low resolution makes critical.

## Only fonts the author was allowed to change

The licensing constraint is stated up front and it shapes the whole collection.

The README says the author has only selected and altered fonts that they have the right to alter because of their licence, for example a free or libre licence or equivalent, and says this is important because it is what allows people to be legally able to freely share and modify these fonts. It adds the observation that it is because of the existing licences that these fonts are available at all.

That last sentence is the important framing. A modified font is a derivative work, and a derivative of a font with a restrictive licence cannot be redistributed freely. So the collection is not a list of the author's favourite typefaces; it is the subset of them that survives the modification.

Attribution is handled rather than stripped out. The README says that where required, font names have been changed, and that any copyright messages included in the font files have been kept, with attribution to the original authors in the document below.

The two Core Collection entries with the clearest licensing story are also the two with named upstream authors. Libron is a modified font based on Newsreader, designed by Production Type, available under the OFL licence, with a separate repository holding the source files. Cartisse is a modified version of XCharter, which is itself an extended version of Bitstream Charter, and it carries an extended copyright notice as part of the font.

The result is a collection where the provenance is legible, which is the right standard for a repository whose whole output is a set of modified derivatives.

## The Core Collection, and why a full style set matters

The Core Collection is described as a selection of the author's very favourite fonts, and the ones considered the highest quality or the best choice for most readers looking for a new font. The examples directory splits the repository into core/ and extra/, so the core is the shortlist and the extra directory holds the rest.

The requirement for a font to enter the Core Collection is stated as a technical bar rather than a taste judgement. Each of these fonts has solid styles for all four font files, Regular, Italic, Bold and Bold Italic, that modern e-readers require, and they have decent glyph coverage, with at least full support for Latin-1 and preferably even more character sets.

That four-style requirement is worth pausing on, because it is a common disappointment with font collections. A font that ships only a regular will render synthetic bold and italic on the device, and synthetic bold on E Ink looks noticeably worse than a real bold, because the rasteriser has to fake a weight increase at low resolution. A font with four real styles renders as the designer intended on a device that cannot compensate.

The Latin-1 baseline matters too, and it is a floor rather than a ceiling. On a device used for books in European languages, Latin-1 covers the accented characters that the language needs, and the author notes that some of the fonts go beyond that.

The three Core entries shown in the README are Libron, Sourcerer and Cartisse, and the notes attached to each say something about why. Cartisse is a modified XCharter with manual modifications to kerning specifically, made for optimal legibility on Kobo devices, and it has its own repository because of that.

One limitation is stated outright: since the repository offers a maximum of four versions for each font family, the original fonts may be a better choice for desktop publishing and similar work.

## The interactive preview site, and the two tools the author pairs it with

There is a separate interactive preview site, a mini website where you can check out the fonts before installing anything.

The preview site lets you customise the font size and the line height, and emulate a device with different colour bezels and display mode, and you can select from all the fonts in the collection. That last point is the useful one for a reader deciding, because the device emulation is doing the thing a physical device would do, which is showing you the font under the contrast and colour conditions of your actual reader rather than on a monitor.

The font size and line height controls are there for the same reason. Line height is the modification that matters most on E Ink, and being able to see the effect before committing to a font saves a lot of flashing and refetching.

Two companion tools are recommended. The first is NickelTypeFix, with the optimizeLegibility option, which the README recommends alongside the KF patched fonts if you want proper kerning, tracking, ligatures and correct justification support. The distinction is important: the patched fonts tend to give better text rendering on Kobo devices, while NickelTypeFix adds the typographic features the patched fonts themselves do not provide.

The second is KOReader, recommended regardless of which e-reader you use, described as giving the most customizable reading experience. On Kobo devices it can be installed through the browser with the KoboPatch Web UI, which is another project by the same author and can help with modifying the device in other ways.

The technical background is in a blog post linked from the README, Patching Fonts for my Kobo, which explains how the repository came to be and is part of a larger series on the changes made to the fonts.

## A personal collection with a release process behind it

The repository layout shows that this is a maintained project rather than a folder of files.

There is a build.py, a local_build.sh script, a BUILD.md, a VERSION file, a CHANGELOG.md, an AGENTS.md, a tools/ directory, a fonts/ directory holding the actual fonts, a docs/ directory, and the examples/ directory with the core and extra categories plus a showcase image. There is also a .gitea/ directory alongside .github/, which suggests the project is mirrored onto a second forge.

The release history confirms the activity. The tags are v2026.08.05 carrying version 4.2, v2026.07.21 with version 4.1, and v2026.07.02 with version 4.0. So the versions are a plain sequence and the tags carry a date, which is a sensible convention for a collection that changes when a font is added or patched rather than when code changes.

The primary language is listed as Python, which is the build tooling, and the topics are boox, e-reader, fonts, kindle, kobo and ofl. The OFL topic is a good sign, because it is the licence family the collection relies on.

The project's own framing is worth quoting in spirit, since it explains the maintenance model. The README asks readers who found the fonts useful to consider starring the repository, which helps the author understand how useful the work has been, and to consider sponsoring, because this is something maintained in the author's free time. That is an honest description of a collection with one maintainer, and it tells you what to expect in terms of how quickly a new device generation gets supported.

## Conclusion

Adopt ebook-fonts if your e-reader renders text poorly with the stock fonts, because the collection exists for exactly that problem and every font in it is patched for E Ink rather than merely rescaled. Do not adopt it expecting a general-purpose typeface library; it is a curated set of patched fonts, and some family names were changed to work around a Kobo bug. Before you pick one, check that your device is a Kobo, Kindle, Pocketbook or Boox, and read the KF tip about NickelTypeFix, because the patched fonts handle text rendering better while the separate tool adds the kerning, tracking, ligatures and justification the patched fonts themselves cannot provide.

## FAQ

### What changes does the ebook-fonts collection make to the original fonts?

For some fonts the family names have been altered, sometimes glyphs have been altered, sometimes metrics have been altered, and sometimes hinting has been modified, all to improve readability on E Ink displays. Name changes are often workarounds, as with Sourcerer, which is renamed because fonts containing a number will not work on Kobo devices due to a bug in Nickel.

### Which e-reader devices do these fonts work on?

The collection was tweaked primarily for Kobo devices, and the README says the fonts can also be used on other devices including Kindle and Pocketbook, and may work well for general use such as word processing. The topics also list boox, kindle and kobo.

### Why were the font family names changed in this collection?

Where required, names were changed so the fonts work correctly on Kobo devices, because fonts containing a number will not work due to a bug in Nickel. Any copyright messages included in the font files have been kept, with attribution to the original authors in the document below.

### How can I preview these fonts before installing them?

There is an interactive preview site where you can select from all the fonts in the collection, customise the font size and line height, and emulate a device with different colour bezels and display mode. The README also recommends KOReader for the most customizable reading experience, and NickelTypeFix with optimizeLegibility for proper kerning, tracking, ligatures and justification.

## Sources

- [Issues](https://github.com/nicoverbruggen/ebook-fonts/issues)
- [nicoverbruggen/ebook-fonts on GitHub](https://github.com/nicoverbruggen/ebook-fonts)
- [Project website](https://nicoverbruggen.be/fonts)
- [README](https://github.com/nicoverbruggen/ebook-fonts/blob/main/README.md)
- [Releases](https://github.com/nicoverbruggen/ebook-fonts/releases)

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Hysen Labs editorial analysis, written from the project's own repository and release notes. Cite the canonical page: https://hysenlabs.com/projects/nicoverbruggen-ebook-fonts