Thorium Reader
Thorium Reader is a free digital book reader and library for ebooks, audiobooks, comics, manga and documents.
What Thorium Reader is
Thorium Reader is a free digital book reader and library for ebooks, audiobooks, comics, manga and documents. It is available for Windows, macOS, Linux, iOS and iPadOS, and supports EPUB, fixed-layout EPUB, PDF, DAISY, Web Publications, audiobook formats such as MP3 and FLAC, and comics in CBZ, EPUB or PDF. Readers can change text size, themes and spacing, select from more than ten fonts, and navigate with keyboard shortcuts. It opens DRM-free publications and Readium LCP-protected titles from compatible sources. Downloaded material works offline, although an LCP-protected file must connect online at least once. Desktop users can add and browse OPDS catalogs, depending on provider options. Accessibility support includes JAWS, NVDA, Narrator and VoiceOver; the iOS accessibility statement notes known VoiceOver limitations with EPUB and PDF reading. Minimum platform versions are listed, including iOS/iPadOS 26, Windows 10, macOS 12 Monterey, Ubuntu 18.04, Fedora 32 or Debian 10. Thorium Reader is developed by EDRLab, a Paris-based non-profit.
Good
- Free on Windows, macOS, Linux and iOS/iPadOS.
- Supports EPUB, PDF, DAISY and audiobooks.
- Text size, themes, spacing and fonts are adjustable.
- Downloaded publications can be used offline.
- Supports JAWS, NVDA, Narrator and VoiceOver.
Watch out
- LCP-protected files need an online connection once.
- iOS VoiceOver has known EPUB and PDF limitations.
- Each platform has a listed minimum version.
Who it suits
Thorium Reader may suit heavy readers, library-goers and students who want one app for several publication types. It is also relevant to readers who need accessibility support or offline access to downloaded material.
Verdict
Thorium Reader combines broad format support with adjustable reading controls and offline use. Check its platform requirements and the noted iOS VoiceOver limitations if those affect your reading setup.
Plans and prices
From Thorium Reader's own pricing page, checked 3 Oct 2026.
| Plan | Price | What it gives you |
|---|---|---|
| Thorium Reader | Free | Free on all platforms |
The facts
Each one read from Thorium Reader's own pages, with the date it was checked.
What it does
- Accessibility
- The site lists support for JAWS, NVDA, Narrator and VoiceOver; its iOS accessibility statement also describes known VoiceOver limitations for EPUB and PDF reading.checked 3 Oct 2026
- Desktop catalogs
- The desktop app can add and browse OPDS catalogs, subject to the catalog provider’s options.checked 3 Oct 2026
- Desktop privacy and network use
- The desktop specification says the app collects no personal data, while describing anonymized telemetry and version checks when network access is available.checked 3 Oct 2026
- DRM and retailers
- It opens Readium LCP-protected publications and DRM-free publications from compatible retailers.checked 3 Oct 2026
- Formats
- The reader supports EPUB, fixed-layout EPUB, PDF, several audiobook formats including MP3 and FLAC, and comics in CBZ, EPUB or PDF.checked 3 Oct 2026
- Offline use
- Downloaded publications can be read or heard offline; LCP-protected files require an online connection at least once.checked 3 Oct 2026
- Reading controls
- Readers can adjust text size, themes and spacing, choose from 10+ fonts, and use keyboard navigation with custom shortcuts.checked 3 Oct 2026
- Security assurances
- The desktop specification says ISO 27001 and SOC 2 Type II assurances apply to content providers’ services, not to Thorium Reader itself.checked 3 Oct 2026
- Support
- The maker links to a Help Desk and Discord; the desktop specification also points users to guides, a public issue tracker and support channels.checked 3 Oct 2026
- What it does
- Thorium Reader is a digital book reader and library for ebooks, audiobooks, comics, manga and documents.checked 3 Oct 2026
- Who it is for
- The desktop technical specification names the general public, with particular attention to heavy readers, library-goers and students.checked 3 Oct 2026
The company
- Headquarters
- Paris, Francechecked 28 Sep 2026
- Maker
- Thorium Reader is developed by EDRLab, a Paris-based non-profit development laboratory created in 2015.checked 3 Oct 2026
Money
- Libraries and free catalogs
- It can read compatible Readium LCP library downloads and content obtained from Project Gutenberg, LibriVox and other public-domain or openly licensed sources.checked 3 Oct 2026
Where it runs
- Platforms and requirements
- It is available for iOS/iPadOS, Windows, macOS and Linux; the site lists iOS/iPadOS 26, Windows 10, macOS 12 Monterey, Ubuntu 18.04, Fedora 32 or Debian 10 as minimum versions.checked 3 Oct 2026
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