What is the AFBOOK file format?
An .afbook file is a book project created with the Books feature in Affinity Publisher 2, the page-layout app from Serif (now owned by Canva). Instead of squeezing a long publication into one document, the Books feature lets you build it from many smaller chapter files. Each chapter is a normal .afpub document, and the .afbook file records which documents belong to the book, the order they appear in, and shared settings such as master pages, text styles, swatches and table formats that keep every chapter looking the same.
Think of the .afbook as the organizing file for the whole project. It links to the chapter files rather than swallowing them, which is what makes large books, manuals and magazines easier to manage and to split between several people. Because those links point at real files on disk, moving or renaming the underlying .afpub documents can break the book.
Security & safety
RISK: LOWAn .afbook is a document project file for a page-layout application and does not contain executable code. The main practical risk is broken links: if the referenced .afpub chapter files are moved, renamed or missing, the book will not assemble correctly. Only open files from sources you trust and keep chapters in the same folder as the book.
Format details
in a nutshellPrograms that open AFBOOK files
Windows1 app
Affinity by Canva (Affinity Publisher)
Free Install the free Affinity app, open the Books panel via Window > Books, choose Open Book from the panel menu and select your .afbook file. 
macOS1 app
Affinity by Canva (Affinity Publisher)
Free Launch Affinity, show the Books panel from Window > Books, then pick Open Book and browse to the .afbook file.
Affinity Publisher 2 for iPad
Free Open the app, use the Books panel to choose Open Book and load the .afbook project along with its chapter files. Technical details
deep spec| Encoding | Binary |
| Container | Book manifest that references one or more external .afpub chapter documents |
| Compression | Not publicly documented |
| Encryption | None documented |
| Structure | An .afbook file records the collection of chapter documents that make up a book: the order of the chapters, plus shared book resources such as master pages, text styles, swatches and table formats used to keep formatting consistent across chapters. The individual chapter layouts stay in their own separate .afpub files; the .afbook itself acts as the organizing project file that links them together. |
| Platforms | Windows, macOS, iPadOS |
| Notes | Created and edited only through the Books panel in Affinity Publisher 2 (Window > Books, or File > New Book). Because chapters are stored as separate linked files, moving or renaming the underlying .afpub files can break the book's references. |
| Integrity | None documented |
| Byte order | Not publicly documented |
| Released | 2024 |
| Latest version | Affinity Publisher 2 |
AFBOOK conversions
Community Q&A
asked by usersNo questions yet - be the first to ask about AFBOOK files.
Frequently asked questions
How do I open an .afbook file?
.afbook file. Keep its .afpub chapter files nearby.What is the difference between .afbook and .afpub?
.afpub is a single Affinity Publisher document. An .afbook is a book project that links several .afpub documents together as chapters and stores the chapter order plus shared styles and master pages.Can I open an .afbook file without Affinity Publisher?
Why does my book show missing chapters?
.afbook file references external .afpub files by their location. If those files were moved, renamed or deleted, the book cannot find them. Restore the files to their original folder or re-link them in the Books panel.How do I turn an .afbook into a single file to send someone?
Is .afbook the same as an ebook file?
.afbook is an editable book layout project, not a finished ebook. To create a reading file you export it to EPUB or PDF from Affinity Publisher.
