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Annotate eBooks with semantic colors

Upload any EPUB file and highlight with the same semantic color-coding you use for PDFs. Your eBook highlights join your unified library: searchable, linkable into your knowledge graph, and exportable to AI tools.

Color definitions
Key concept12
Question8
Evidence15
Methodology6

How it works

Three steps to get started

01

Upload your EPUB

Drag in any EPUB file. Highlyt extracts the text client-side using JSZip, sanitizes HTML with DOMPurify, and renders it in a clean reading view.

02

Highlight like any PDF

Select text, choose a color, add notes. The same semantic color system works across PDFs and EPUBs. Your color definitions carry over from document to document.

03

Search across formats

EPUB highlights appear in the same search results as PDF highlights. Link an idea from an eBook to a research paper. Your knowledge graph doesn't care about file formats.

Who it's for

Built for how you actually read

Students

Annotate course eBooks

Many university textbooks come as EPUBs. Upload them to Highlyt and get the same semantic highlighting, search, and AI integration you use for PDF papers.

Researchers

Include eBook sources in reviews

Some foundational texts are only available as EPUBs. Highlyt lets you include them in your literature review alongside PDFs. Link frameworks across formats seamlessly.

Book readers

Highlight non-fiction eBooks

Upload your DRM-free eBooks from Humble Bundle, Standard Ebooks, or any publisher. Get the semantic highlighting and knowledge graph that Apple Books and Kindle don't offer.

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FAQ

Frequently asked questions

What EPUB formats are supported?+

Highlyt supports standard EPUB files (.epub). The text is extracted client-side and rendered in a clean reading view. DRM-protected EPUBs cannot be processed.

Can I link EPUB highlights to PDF highlights?+

Yes. Cross-document linking works across all source types: PDFs, EPUBs, web clips, and YouTube transcripts. Your knowledge graph is format-agnostic.

Do EPUB highlights appear in search?+

Yes. EPUB text is indexed into the same search system as PDFs. Search results include EPUB highlights alongside PDF highlights with page numbers and snippet previews.

Your next book deserves better than a yellow highlighter

Every book and paper you read builds your knowledge. Highlyt makes sure none of it gets lost. Start your free trial and turn scattered highlights into a connected, searchable, AI-ready knowledge base.

Knowledge graph that grows with youClaude and ChatGPT read your highlightsEvery color carries your reasoning