Free online PDF to EPUB converter

An e-reader, library app, or publishing system may accept EPUB but reject PDF, creating a need to convert the file. The conversion changes a fixed page layout into reflowable content, so complex documents usually need inspection and correction afterward.

What the PDF format is

PDF, originally developed by Adobe, stores a document as a fixed visual layout containing text, fonts, vector graphics, raster images, and positioning instructions. It is used for manuals, forms, invoices, academic papers, scanned books, government documents, and print-ready files that must retain the same appearance across systems.

PDFs can be created by Adobe Acrobat, Microsoft Word, LibreOffice, web browsers, scanners, desktop-publishing software, and virtual PDF printers. A file may contain selectable text, scanned page images, or both. Image-only pages require optical character recognition (OCR) before they can become editable EPUB text.

Password-protected or permission-restricted PDFs may need to be unlocked by the owner before conversion. Do not remove protection from a file without authorization.

What the EPUB format is

EPUB is a ZIP-based ebook container that normally includes XHTML content, CSS, images, fonts, navigation, and package metadata. Most EPUB 3 books use reflowable content: the reading app changes line breaks, page count, margins, and sometimes font size to fit the screen.

EPUB works with applications such as Apple Books, Thorium Reader, Adobe Digital Editions, Kobo software, and many dedicated e-readers. Compared with PDF, a well-structured reflowable EPUB usually offers adjustable text size, searchable text, bookmarks, navigation, accessibility features, and smaller files for text-heavy books.

EPUB also supports fixed-layout publications, which preserve page geometry for comics, illustrated books, and complex designs. Fixed-layout EPUB requires compatible reading software and does not provide the same reflow and resizing benefits as a standard reflowable book.

How to convert a PDF to EPUB

Use the built-in online converter

1. Open the PDF-to-EPUB converter on 101convert.com; it can be used without installing software.
2. Select or upload the source .pdf file.
3. Choose EPUB as the output format and start the conversion.
4. Download the generated .epub file and open it in an EPUB reader.
5. Check the reading order, headings, table of contents, images, page breaks, links, and special characters.

Use online processing only for documents whose confidentiality requirements permit uploading. Contracts, medical records, unpublished manuscripts, and other sensitive files should be processed locally unless the service's storage and deletion terms are acceptable.

Use Calibre on a desktop

Calibre is a desktop ebook manager with PDF-to-EPUB conversion. Install it from the official Calibre distribution, then:

1. Open Calibre and choose Add books to import the PDF.
2. Select the book and choose Convert books.
3. Set Output format to EPUB.
4. Correct the title, author, language, cover, and other metadata.
5. In PDF Input, change spacing, header, and footer options only when the source requires it. Removing headers or footers can also remove meaningful content.
6. Select OK, then use Save to disk to export the EPUB.

Calibre generally performs best with a clean text layer and a simple, single-column PDF. It cannot reliably reconstruct every layout built from columns, text boxes, floating objects, or absolute page positioning.

Run OCR on scanned pages

If words cannot be selected or copied, run OCR before conversion. In Adobe Acrobat, use Scan & OCR → Recognize Text. OCRmyPDF can add a searchable text layer from the command line:

ocrmypdf --deskew input.pdf searchable.pdf

Convert searchable.pdf rather than the image-only original. Review the EPUB for errors in ligatures, hyphenated words, columns, footnotes, tables, equations, and characters with similar shapes.

Rebuild from the original source

For a publication-quality result, obtain the original DOCX, ODT, HTML, or Markdown source instead of inferring structure from the PDF. Clean the headings, paragraphs, links, images, and metadata in the source document, then export or package it as EPUB.

LibreOffice can export an open document through File → Export As → Export as EPUB. Pandoc can convert a structured DOCX file with:

pandoc source.docx -o book.epub --toc

Source-based conversion preserves document structure more reliably than PDF conversion because headings and paragraphs already exist instead of being inferred from page coordinates.

Quality and compatibility limitations

PDF is page-oriented; EPUB is generally flow-oriented. Multiple columns, sidebars, text boxes, floating captions, bleed areas, precise page breaks, and decorative positioning can produce the wrong reading order or separate captions from their images.

Tables, footnotes, equations, forms, annotations, bookmarks, embedded media, hyperlinks, and accessibility metadata may be lost or altered. Scanned text can contain OCR mistakes even when the resulting EPUB appears visually correct. Fonts may also be substituted if they are not embedded or cannot be redistributed.

Validate an EPUB intended for distribution with EPUBCheck. Test it in at least one desktop reader and one mobile or e-reader application, checking the cover, metadata, language, navigation, links, image resolution, font rendering, reading order, and chapters that cross the original page boundaries.

Keep the original PDF for archival or print use. Treat the EPUB as a separately edited reading edition when the source contains OCR, complex page design, forms, or technical notation.