What is EPUB dark mode?

EPUB dark mode is a display setting in your e-reader or reading app that changes the background from white to black (or dark grey) and the text from black to white or light grey. It reduces screen brightness and blue light emission in low-light environments, which helps reduce eye strain for reading at night or in bed. Most EPUB readers implement dark mode at the app level, so it applies to any EPUB you open.

Does dark mode work on converted EPUBs from toolkit.bot?

Yes. toolkit.bot produces standard EPUB3 files with no embedded background or foreground colour overrides. This means the reader app's dark mode setting applies cleanly — text turns white, background turns dark, and the reading experience adapts correctly. Some poorly-formatted EPUBs with hardcoded background colours resist dark mode; toolkit.bot-converted EPUBs don't have this issue.

Why does PDF dark mode look worse than EPUB dark mode?

PDF dark mode typically works by inverting the entire rendered page — including images, tables, and graphics. This produces bright-on-dark images that often look unnatural. Some PDF readers apply a 'sepia invert' or smart invert, but it's imperfect. EPUB dark mode works at the text layer: the app changes CSS background and text colours cleanly, leaving images in their natural state (or with a subtle dim). The result is much more comfortable.

How do I enable dark mode on Kindle?

On Kindle e-readers: tap the top of the screen to open the toolbar, tap the sun/brightness icon, then toggle 'Dark mode' or select the black background theme. On Kindle app (iOS/Android): open a book, tap the screen to show controls, tap the 'Aa' font button, and select the black or dark theme under 'Background color'. The dark setting persists across books.

How do I enable dark mode on Kobo?

On Kobo e-readers: open a book, tap the centre of the screen, tap the 'A' text settings icon, scroll to 'Colour scheme' or 'Background colour', and select Night (black background, white text). On the Kobo app (iOS/Android): open a book, tap to show controls, tap the 'Aa' settings button, and select the dark theme. Kobo also has an amber ComfortLight setting that warms the screen independently of the dark mode colour scheme.

EPUB Dark Mode — How to Enable and Customise Dark Reading on Kindle, Kobo, and Reading Apps (2026)

Updated June 2026 · General

EPUB dark mode — white text on a dark background — is the standard setting for reading in bed, in low-light rooms, or any time a bright white screen feels uncomfortable. Every major e-reader and reading app supports it. EPUB handles dark mode better than PDF because the app applies colour changes at the text layer, not by inverting a rendered page image. Here's how to enable dark mode on each major platform and why starting with EPUB (rather than PDF) gives the best result.

Dark mode support across EPUB readers

Platform	Dark mode name	Where to find it	Affects images?
Kindle e-reader	Dark mode	Toolbar → Brightness icon → Dark mode	Images stay natural
Kindle app (iOS/Android)	Black theme	Open book → Aa → Background color → Black	Images stay natural
Kobo e-reader	Night mode	Open book → A → Colour scheme → Night	Images stay natural
Kobo app (iOS/Android)	Dark theme	Open book → Aa → Dark	Images stay natural
Apple Books (iOS/macOS)	Night theme	Open book → Aa → Theme → Night	Images stay natural
Moon+ Reader (Android)	Night mode	Settings → Reading display → Night mode	Optional dim
Lithium (Android)	Dark theme	Menu → Appearance → Dark	Images stay natural
Readwise Reader	Dark mode	Account settings → Display → Dark	Images stay natural

Why EPUB dark mode works better than PDF dark mode

Text-layer colour change — EPUB apps change CSS background and text colours directly. PDF apps invert the rendered bitmap, which often distorts diagrams and figures.
No hardcoded colours — toolkit.bot-converted EPUBs use no embedded background colours, so the reader's dark mode applies cleanly every time.
Font settings still work — in dark mode EPUB, you can still adjust font size, family, and spacing. PDF dark mode is purely visual and doesn't affect layout.
Images look natural — EPUB readers leave images in their original state (or subtly dimmed) in dark mode. PDF inversion turns chart backgrounds black and inverts photo colours.

How to get a PDF into EPUB dark mode

Go to toolkit.bot/pdf2epub and upload your PDF
Download the EPUB
Send to Kindle via email, transfer to Kobo by USB, or import into Apple Books / your preferred EPUB app
Open the EPUB, tap the display settings, and enable dark / night mode

Frequently asked questions

What is EPUB dark mode?: EPUB dark mode is a display setting in your e-reader or reading app that changes the background from white to black (or dark grey) and the text from black to white or light grey. It reduces screen brightness and blue light emission in low-light environments, which helps reduce eye strain for reading at night or in bed. Most EPUB readers implement dark mode at the app level, so it applies to any EPUB you open.
Does dark mode work on converted EPUBs from toolkit.bot?: Yes. toolkit.bot produces standard EPUB3 files with no embedded background or foreground colour overrides. This means the reader app's dark mode setting applies cleanly — text turns white, background turns dark, and the reading experience adapts correctly. Some poorly-formatted EPUBs with hardcoded background colours resist dark mode; toolkit.bot-converted EPUBs don't have this issue.
Why does PDF dark mode look worse than EPUB dark mode?: PDF dark mode typically works by inverting the entire rendered page — including images, tables, and graphics. This produces bright-on-dark images that often look unnatural. Some PDF readers apply a 'sepia invert' or smart invert, but it's imperfect. EPUB dark mode works at the text layer: the app changes CSS background and text colours cleanly, leaving images in their natural state (or with a subtle dim). The result is much more comfortable.
How do I enable dark mode on Kindle?: On Kindle e-readers: tap the top of the screen to open the toolbar, tap the sun/brightness icon, then toggle 'Dark mode' or select the black background theme. On Kindle app (iOS/Android): open a book, tap the screen to show controls, tap the 'Aa' font button, and select the black or dark theme under 'Background color'. The dark setting persists across books.
How do I enable dark mode on Kobo?: On Kobo e-readers: open a book, tap the centre of the screen, tap the 'A' text settings icon, scroll to 'Colour scheme' or 'Background colour', and select Night (black background, white text). On the Kobo app (iOS/Android): open a book, tap to show controls, tap the 'Aa' settings button, and select the dark theme. Kobo also has an amber ComfortLight setting that warms the screen independently of the dark mode colour scheme.