500 KB EPUB sample

An EPUB file of exactly 512,000 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 500 KB sample, test or dummy EPUB file.

sample-epub-500kb.epub

500 KB512,000 bytes

Download 500 KB EPUB

Created in your browser in a few seconds, then checked against the SHA-256 checksum. The file is not uploaded anywhere. No sign-up.

Type: application/epub+zip
SHA-256: 53cd3d54244345211b9d7faf850375ea614846f766222b6fe714e0d3be5571cb
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 512,000 bytes. Padding of 18 bytes in a PNG tEXt comment chunk inside the image makes up the rest.

EPUB version	3.0
Chapters	12
Embedded image	PNG, 471 × 351 px
Navigation	EPUB 3 nav document
DRM	None
Container	ZIP (OCF)

First bytes of the file

The first 64 bytes of sample-epub-500kb.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 500 KB matters

A 512,000-byte file: larger than most API body limits, smaller than most upload limits. These are the default limits a file of this size is useful for testing:

System	Limit	Note
Amazon DynamoDB items	400 KB per item	500 KB cannot be stored as a single item.
Express body parsers	100 KB by default	Rejected unless the limit is raised.
nginx request body	1 MB by default (client_max_body_size)	Accepted with room to spare.

All 500 KB sample files

Use this file for

Checking email size handling
Testing conversion to other formats
Testing e-book upload and ingestion

Testing notes for EPUB

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

EPUB format reference

Technical details

File name	sample-epub-500kb.epub
Format	EPUB (EPUB e-book)
Extension	.epub
MIME type	application/epub+zip
Size	512,000 bytes (500 KB)
Kind	Binary
Signature	50 4B 03 04
SHA-256	53cd3d54244345211b9d7faf850375ea614846f766222b6fe714e0d3be5571cb
Created	2026-10-23
Validation	See 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.
Preview	Not available for this file; details only
Source	Generated in your browser by this site's generator; not copied from elsewhere
Licence	Free to use, modify and redistribute (terms)
Category	Ebooks

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-500kb.epub     # Linux
shasum -a 256 sample-epub-500kb.epub # macOS

On Windows, run Get-FileHash sample-epub-500kb.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 500 KB?: Yes. It is 512,000 bytes, which is 500 KB in the binary units that operating systems and server limits use (1 KB = 1,024 bytes).
What is inside the 500 KB 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 512,000 bytes. Padding of 18 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.

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