PDF to MOBI Converter

How to Convert PDF to MOBI Online

1. Upload Your PDF: Drag and drop or click "+ Add Files" to select PDFs from your computer. Batch is supported — drop several PDFs in and each one converts in parallel.
2. Confirm MOBI as the Output Format: MOBI is preselected. The conversion produces a reflowable e-book with text content, headings, basic styling, lists, and embedded images carried over from the PDF. Defaults are tuned for Kindle reading — keep them unless you have a specific need.
3. Review the Advanced Options (Optional): Defaults are optimised for typical PDFs. The panel notes "Our defaults are optimized for the best results. We recommend you keeping the defaults unless you have a specific need." Heavy or complex PDFs (multi-column journals, scanned books, magazine layouts) often convert better when you split the PDF first or try PDF to EPUB as an alternative target.
4. Convert and Download: Click "Convert" and download the .mobi file. Sideload it onto your Kindle by USB or transfer it through your preferred Kindle library tool. Files are uploaded over an encrypted connection, processed on our servers, and deleted automatically after a few hours — no sign-up, no watermark, never shared.

Why Convert PDF to MOBI?

MOBI is the legacy Mobipocket e-book format Amazon acquired in 2005 and used as the foundation for Kindle. It is built for reflowable text — the reader can change font, size, line spacing, and orientation, and the page repaints to fit the screen. PDF, by contrast, is a fixed-layout print format. On the 6" or 7" screen of a Kindle Paperwhite or Oasis a raw PDF is usually too small to read without constant zoom-and-pan. Converting to MOBI hands the layout decisions back to the reader. Common reasons to convert:

• Reading PDFs on older Kindles — Kindle Keyboard, Touch, Paperwhite 1-4, Voyage, and basic Kindles all open MOBI natively. Many of these models can technically display a PDF but the text is tiny, there is no font scaling for the embedded glyphs, and bookmarks/dictionary lookup don't work. MOBI gives you the full Kindle reader features on those devices.
• Keeping pre-2023 e-book libraries playable — Many readers still have large MOBI libraries collected before Amazon shifted to EPUB. Adding a new PDF as MOBI keeps the whole collection in one format and one folder structure on the device.
• Sideloading via USB or Calibre — Amazon's Send to Kindle service stopped accepting MOBI in late 2023, but MOBI still works perfectly when copied to the Kindle's documents folder over USB or pushed through a tool like Calibre. Many readers prefer this because it skips Amazon's cloud entirely.
• Long-form reading from PDFs originally meant for desktop — Academic papers, white papers, government reports, and product manuals are frequently distributed only as PDF. Converting to MOBI turns them into a comfortable evening-reading format with adjustable type and progress tracking.
• Better battery and lower memory use — Reflowable MOBI files render with the Kindle's native text engine, which uses far less RAM than rasterising a PDF page-by-page. On entry-level Kindles this is the difference between smooth page turns and visible lag.
• Archive format for documents you want to keep readable — MOBI is well-documented and supported by every major e-reader app on iOS, Android, and desktop (Kindle for PC/Mac, Calibre, FBReader, KOReader). Even though Amazon is sunsetting it, the readers will keep opening it.

MOBI vs EPUB vs PDF for Kindle

If you have a newer Kindle (2022+) or want broader e-reader support, PDF to EPUB is usually the better target. MOBI remains the right choice when you specifically need maximum compatibility with older Kindle hardware or want to drop the file into a long-standing MOBI library.

What Converts Well — and What Doesn't

For scanned PDFs, run OCR first so the converter has real text to reflow rather than page images. For multi-column journal articles, single-column extraction or reading on a larger device (Kindle Scribe, tablet) usually beats forcing reflow.

Frequently Asked Questions

Will the original PDF layout be preserved?

No, and that is the point of MOBI. The format is reflowable: text wraps to the Kindle's current font size, page width, and orientation. Headings, bold/italic, paragraph breaks, lists, and inline images survive. Exact pixel positioning, multi-column layouts, headers/footers, and footnote anchoring at the bottom of a page do not — they get re-laid out as a single column of running text. If preserving the printed page exactly matters more than reflow comfort, keep it as PDF.

Can I still send MOBI files to my Kindle?

Not through Amazon's Send to Kindle email or web upload — Amazon ended MOBI support there on December 20, 2023, and the official Send to Kindle supported formats list now shows EPUB, PDF, DOC/DOCX, TXT, RTF, HTM/HTML, and common image formats. MOBI still works by USB sideload (drag the file into the Kindle's documents folder when connected by cable) and through third-party library tools like Calibre.

Should I use MOBI or EPUB for my Kindle?

For a Kindle Paperwhite 5, Oasis 3, Scribe, or any Kindle bought new from late 2022 onward, EPUB through PDF to EPUB is usually the better choice — Amazon recommends it, Send to Kindle accepts it, and it works on other readers too. For older Kindles (Paperwhite 1-4, Voyage, Keyboard, basic Kindles from 2011-2021) or any sideload workflow, MOBI is the safer pick. Both formats reflow text comfortably; the difference is purely about transfer method and device generation.

What happens to images, tables, and footnotes during conversion?

Images embed inline at the position they appear in the PDF and scale to the Kindle's screen width — they don't reflow but the surrounding text does. Simple tables usually convert to rendered images of the original table, which means they stay readable but you can't change font size for the table contents. Footnotes often become inline parenthetical text rather than clickable references; if footnote fidelity matters, consider PDF to EPUB, which generally handles footnote linking better.

How do I read the converted MOBI on a Kindle without Send to Kindle?

Connect the Kindle to your computer with the supplied USB cable. It mounts as a drive — open the documents folder and drop the .mobi file in. Eject and disconnect; the book shows up in your library on the next sync. The same MOBI file also opens in Kindle for PC, Kindle for Mac, Kindle iOS/Android apps, Calibre, KOReader, and FBReader.

My PDF is a scanned book — will conversion work?

Partially. A scanned PDF contains images of text rather than text itself, so the MOBI output also embeds those images and you lose reflow, font scaling, search, and copy/paste. Run OCR on the PDF first — most modern PDF editors and free tools include OCR — so the file contains a real text layer. After OCR the PDF to MOBI conversion produces a properly reflowable e-book.

Can I convert encrypted or password-protected PDFs?

Password-protected PDFs need the open password removed first; the converter cannot read encrypted content. PDFs with permissions restrictions (no-copy, no-print) but no open password generally convert without issue. DRM-protected PDFs (rare outside enterprise distribution) are not supported.

Is there a file size or page count limit?

The converter handles large PDFs including multi-hundred-page technical books and reference manuals. Conversion happens on our servers, so the practical limit is upload size and connection speed rather than a hard server cap. Very large books (1,000+ pages, heavy image content) take longer to upload than to convert — splitting them or using Compress PDF first usually speeds things up.

Can I convert in the other direction?

Yes — see MOBI to PDF for the reverse, or MOBI to EPUB if you're migrating an older MOBI library to a newer Kindle or another e-reader. If you started in Word rather than PDF, DOCX to MOBI usually produces cleaner reflow than going through PDF as an intermediate.