Best EPUB Readers for Windows (Free) — 2026 Comparison
Windows doesn't have a built-in EPUB reader — Microsoft removed the Edge EPUB feature in 2018. But there are several excellent free options. Here's what works best depending on how you read.
1. Thorium Reader (recommended for most users)
Best for: Comfortable reading, accessibility, EPUB 3.x support
- Built by the EDRLab consortium — the same team that maintains the EPUB standard
- Full EPUB 3.x support including reflowable text, fixed layout, audio, and media overlays
- Excellent accessibility: NVDA and JAWS screen reader support, WCAG 2.1 AA interface
- Reading progress, bookmarks, highlights, and annotations
- Available from the EDRLab website or Microsoft Store
Best choice for accessibility teams, researchers, and general readers who want the most standards-compliant experience.
2. Calibre (best for managing a library)
Best for: Managing large ebook collections, format conversion
- Free, open source, desktop app — download from calibre-ebook.com
- Built-in EPUB viewer with font controls, table of contents navigation
- Converts between ebook formats (EPUB, MOBI, AZW3, PDF, etc.)
- Library management: metadata editing, cover art, series tracking
The viewer is functional but not as polished as Thorium. Best if you also want to manage and convert files, not just read. Note: Calibre converts EPUBs well but struggles with PDF-to-EPUB for complex layouts. See Calibre vs toolkit.bot →
3. Sumatra PDF (lightweight, fast)
Best for: Fast loading, minimal interface, power users
- Tiny install, opens instantly — also reads PDF, DjVu, CBZ/CBR
- Keyboard-driven; good for reading without mouse
- No library management, no annotations beyond basic highlights
- Download from sumatrapdfreader.org
4. Microsoft Edge (browser EPUB support via extension)
Edge removed native EPUB support in 2018 but you can re-enable it via the ePub Reader extension from the Microsoft Store. Works for quick reads but lacks features like highlighting and offline library management.
5. Read on your phone or tablet instead
Many Windows users find it more comfortable to read on a phone or tablet anyway. For iPad, see the iPad guide →; for Android, see the Android guide →.
Getting EPUBs onto Windows
If you have a PDF you want to read on Windows, convert it to EPUB first:
- Go to toolkit.bot/pdf2epub in any browser
- Upload your PDF — conversion takes 15–60 seconds
- Download the EPUB to your Downloads folder
- Open with Thorium Reader or drag into Calibre
Why convert first? EPUB text reflows to your preferred font size and width. PDF on Windows forces you to zoom and scroll horizontally — especially bad for academic papers and textbooks. EPUB vs PDF comparison →
Convert your PDF to EPUB — open it in Thorium Reader on Windows.
Convert PDF to EPUB →