10 MB EPUB sample

An EPUB file of exactly 10,485,760 bytes. It is a valid EPUB e-book file, generated by this site. Compare its checksum and test it with the parser used by your application. Use it wherever you need a 10 MB sample, test or dummy EPUB file.

Download

sample-epub-10mb.epub

10 MB10,485,760 bytes

Download 10 MB EPUB

Created in your browser in a few seconds, then checked against the SHA-256 checksum. No sign-up.

Type
application/epub+zip
SHA-256
e388ce0a299bba5e6dc475fd4d1ae5016cf3e5d70ae46caaf44ec16c5538bf4e
Delivery
Created in your browser from static generator assets (how it works).

What is in this file

A reflowable EPUB 3 book with 12 XHTML chapters, a stylesheet, a navigation document and one test-card PNG that is stored uncompressed and sized so that the book is exactly 10,485,760 bytes. Padding of 1,030,267 bytes in a PNG tEXt comment chunk inside the image makes up the rest.

EPUB version3.0
Chapters12
Embedded imagePNG, 2,048 × 1,536 px
NavigationEPUB 3 nav document
DRMNone
ContainerZIP (OCF)

First bytes of the file

The first 64 bytes of sample-epub-10mb.epub as a hex dump: offset, bytes, then the same bytes as text. The EPUB signature is 50 4B 03 04.

00000000  50 4b 03 04 0a 00 00 00  00 00 00 00 21 5c 6f 61 |PK..........!\oa|
00000010  ab 2c 14 00 00 00 14 00  00 00 08 00 00 00 6d 69 |.,............mi|
00000020  6d 65 74 79 70 65 61 70  70 6c 69 63 61 74 69 6f |metypeapplicatio|
00000030  6e 2f 65 70 75 62 2b 7a  69 70 50 4b 03 04 14 00 |n/epub+zipPK....|

Preview

EPUB files cannot be shown in a browser. Download the file and open it in an application that reads EPUB, such as Apple Books, Kobo and Google Play Books.

Where 10 MB matters

A 10,485,760-byte file: over the default limits of PHP, API Gateway and Spring Boot requests. These are the default limits a file of this size is useful for testing:

SystemLimitNote
Amazon API Gateway10 MB payloadA 10 MB file in a multipart or base64 body is over the limit.
Spring Boot multipart10 MB per request by default (max-request-size)Exceeded once form overhead is added.
PHP8 MB POST body by default (post_max_size)Rejected before the script runs.
Amazon S3 multipart upload5 MiB minimum part sizeThis file splits into exactly two minimum-sized parts.
Email attachmentsCommonly 20 to 25 MB per message10 MB fits, at about 13.3 MB once encoded.

All 10 MB sample files

Use this file for

  • Testing image resizing and memory use
  • Checking reading-system rendering
  • Testing conversion to other formats

Testing notes for EPUB

  • Re-zipping an EPUB with a generic tool usually compresses or reorders the mimetype entry, which makes strict readers reject the book.
  • EPUB content is HTML, so a reading system that renders it in a web view needs the same script protections as a browser.

EPUB format reference

Technical details

File namesample-epub-10mb.epub
FormatEPUB (EPUB e-book)
Extension.epub
MIME typeapplication/epub+zip
Size10,485,760 bytes (10 MB)
KindBinary
Signature50 4B 03 04
SHA-256e388ce0a299bba5e6dc475fd4d1ae5016cf3e5d70ae46caaf44ec16c5538bf4e
Created2026-10-23
ValidationSee the listed size and SHA-256. Small downloads are checked in the browser; verify streamed downloads manually. A hash match does not prove parser compatibility.
PreviewNot available for this file; details only
SourceGenerated in your browser by this site's generator; not copied from elsewhere
LicenceFree to use, modify and redistribute (terms)
CategoryEbooks

Check the stated structure and checksum against your application requirements. As with any download, scan the file with your own security tools before opening it. How files are made and checked

Verify your copy

This file is created in your browser, so it has no direct URL for curl or wget. The generator is designed to produce reproducible bytes. After saving, compare the checksum with the SHA-256 value above.

sha256sum sample-epub-10mb.epub     # Linux
shasum -a 256 sample-epub-10mb.epub # macOS

On Windows, run Get-FileHash sample-epub-10mb.epub -Algorithm SHA256 in PowerShell. For scripts and pipelines, save the file once and keep your own copy.

Related files

Questions about this file

Is this file exactly 10 MB?
Yes. It is 10,485,760 bytes, which is 10 MB in the binary units that operating systems and server limits use (1 KB = 1,024 bytes).
What is inside the 10 MB EPUB file?
A reflowable EPUB 3 book with 12 XHTML chapters, a stylesheet, a navigation document and one test-card PNG that is stored uncompressed and sized so that the book is exactly 10,485,760 bytes. Padding of 1,030,267 bytes in a PNG tEXt comment chunk inside the image makes up the rest.
Do the sample e-books have DRM?
No. They are unencrypted EPUB 3 files with a navigation document, a stylesheet and one image.