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📚 Ebook Converter & Inspector

Unpack EPUB ebooks, read real book metadata (Author, Title, Chapter count) from the archive, and convert to MOBI for Kindle, EPUB, PDF, HTML, or TXT. PDF books can be converted to EPUB and MOBI too.

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Drag & Drop Ebook or PDF File

Supports EPUB, PDF, TXT, HTML ebook documents (Max 30MB)

Ebook Conversion & Reading

Extract chapter text from EPUB ebooks client-side, inspect author metadata and table of contents, and convert your books into MOBI files for Kindle sideloading, standards-compliant EPUB packages, clean printable PDF documents, or plain text for reading anywhere. PDF books are routed through the conversion server's text extractor, then rebuilt as EPUB or MOBI with a generated table of contents.

Note on Kindle: Amazon's Send to Kindle service now accepts EPUB directly and no longer takes MOBI. Choose MOBI when sideloading over USB to an older Kindle, and EPUB for Send to Kindle or any other reader. Output is text and structure only — images, fonts, and original page layout are not carried over.

That last point decides whether this tool suits a given book. EPUB and MOBI are reflowable formats: the reader chooses the typeface and size, and text re-wraps to fit whatever screen it lands on. A novel, an essay collection or a report survives that transformation intact, because the words carry the meaning and the layout was only ever a container. A cookbook built around photographs, a textbook with diagrams beside the paragraphs they explain, or a technical manual with wide code listings will lose the part that made it readable.

Starting from PDF is the harder direction, and it helps to know why. A PDF fixes text at coordinates on a fixed page; converting to EPUB means discarding that page and letting the text reflow. Running headers, footers and page numbers were placed for a printed page and have no equivalent in a reflowable book, so they can surface as stray lines in the text. Two-column academic PDFs are the most difficult case of all, since reading order has to be inferred from position. Expect to skim the result before settling in with it.

Chapter structure comes from the source. An EPUB with a proper table of contents keeps its chapter breaks through conversion; a PDF has none to keep, so a table of contents is generated from the text instead and will be rougher than one an author wrote. If a converted book opens as a single unbroken chapter, that is usually the source telling you it never carried the structure to begin with.

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🔒 Privacy Policy

Last updated: July 16, 2026

1. Absolute Client-Side Privacy

At UnitsSwitch, your privacy is our primary commitment. We build utilities that process calculations directly in your browser. Your files, numbers, texts, or data inputs are never uploaded to our servers, nor do we track your content. All operations, conversions, formatting, and calculations happen 100% locally on your device CPU/GPU cores.

2. Server-Side Fallbacks

For operations that require remote processing (such as real-time currency exchange rates or advanced backend file transcodings), we request data from public endpoint routes. When utilizing these APIs:

We do not collect IP addresses or log transaction histories.
Temporary file transfers occur over highly secure HTTPS channels and are automatically purged upon conversion completion.

3. Local Storage Usage

We use standard web browser localStorage to store your pinned favorite tools and recent conversion history. This data is stored strictly on your local browser profile and never synchronized to any remote host. You can clear this history at any time using the "Clear All" button in the History tab.

4. Analytics & Cookies

We do not use tracking cookies or behavioral profile engines. We believe in a clean, non-intrusive utility experience.

5. Contact

For any inquiries regarding this policy, feel free to inspect our source files or contact us directly.

📜 Terms of Service

Last updated: July 16, 2026

1. Terms Acceptance

By using the UnitsSwitch application, you agree to comply with and be bound by these Terms of Service. If you do not agree, please discontinue usage immediately.

2. Permitted Use

UnitsSwitch is provided as a general-purpose unit conversion, calculation, formatting, and micro-editing dashboard. You may use it for personal, educational, or commercial purposes. Any automated scrapers, denial of service attacks, or reverse-proxy bypasses targeting our remote API fallbacks are strictly prohibited.

3. Disclaimer of Warranties

UnitsSwitch is provided "as is" without warranty of any kind. While we calibrate all physical factors, electrical values, and currency conversion logic to international and commercial standards, we do not guarantee absolute mathematical precision or real-time trading accuracy. You use all calculations at your own discretion.

4. Service Limitations

We reserve the right to modify or discontinue any tool, category, database API route, or local compilation library at any time without prior warning.

5. Governing Law

These terms shall be governed by and construed in accordance with the laws of your local jurisdiction, without regard to conflict of law principles.

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