Contents, history, and search
Navigate nested tables of contents, reopen eight recent books, and search the full text. Chapter-grouped snippets lead directly to each matching passage.
Native EPUB reader / C++ + Qt
Spindle
Keep the book's shape.
Make the reading yours.
A native EPUB reader that respects vertical and horizontal writing, fonts, images, and fixed layouts while bringing search, annotation, read-aloud, and local AI translation into one reading space.
風吹けば
花びらは
頁をわたり
Chapter 03
A native reading view preserves the book’s own typography, images, and rhythm.
12 / 2801 / Read as designed
Bring the EPUB's expression
directly to the reading view.
Spindle uses Qt WebEngine and a custom epub:// URL scheme to load the book's CSS, embedded fonts, and images as authored. Japanese vertical writing and horizontal layouts follow the direction and typography specified by the publication.
Fixed-layout books fit complete pages without changing their aspect ratio, with spreads, binding direction, and page placement respected. Reflowable books can wrap to the window or a chosen line measure for a more personal reading width.
02 / Reading tools
Read, find, and remember
beside the book.
Highlights and notes
Select from six highlight colors and attach notes. Marks remain character-precise in vertical text and on the original or translation side, with Markdown and JSON export.
Read aloud and audio export
Use operating-system voices, VOICEVOX, or Piper to speak the chapter paragraph by paragraph. Follow the spoken passage, continue to the next chapter, or export WAV, MP3, and M4A audio.
Themes and comfort
Light, sepia, and dark themes remember separate brightness for page, original, and translated text. Adjust fonts, zoom, line measure, and sidebar state, then return to the last chapter.
03 / Local AI
Translate and summarize
without sending the book away.
Connect to a locally running Ollama instance to translate or summarize a chapter or selection. Choose original, bilingual, or translation-only display, and reopen cached results instantly for each book and target language.
A per-book glossary keeps character names and technical terms consistent. Generate glossary candidates from a chapter or entire book, then export a new bilingual or translated EPUB without modifying the original file.
ORIGINAL
↓ local / OllamaThe book keeps its own voice and shape.
TRANSLATION
cached beside the EPUB本は、それ自身の声とかたちを保ちます。
Keep the book, shape the reading
Preserve the work.
Personalize the reading.
Find releases and build instructions for Windows, macOS, and Linux on GitHub.
Explore Spindle on GitHub ↗