20 MB XLSX sample

An XLSX file of exactly 20,971,520 bytes. It is a valid Excel workbook (Office Open XML) file, generated by this site. Compare its checksum and test it with the parser used by your application. Use it wherever you need a 20 MB sample, test or dummy XLSX file.

sample-xlsx-20mb.xlsx

20 MB20,971,520 bytes

Download 20 MB XLSX

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

Type: application/vnd.openxmlformats-officedocument.spreadsheetml.sheet
SHA-256: 94b8d14c535362f4a61c91dc2fcbac1ad73d577c15eec9ecb25c00ef9ff88be0
Delivery: Created in your browser from static generator assets (how it works).

What is in this file

One worksheet with a bold, frozen header row and 225,499 rows of fictional orders: text, dates, numbers and a formula in every row. 2,085 bytes of text in the workbook description property bring the file to the exact size.

Sheets	1 (Orders)
Data rows	225,499
Columns	9
Formulas	225,499 (total = quantity × unit price)
Frozen panes	Header row
Macros	None
Container	ZIP (Office Open XML)

First bytes of the file

The first 64 bytes of sample-xlsx-20mb.xlsx as a hex dump: offset, bytes, then the same bytes as text. The XLSX signature is 50 4B 03 04.

00000000  50 4b 03 04 14 00 00 00  08 00 00 00 21 5c 19 27 |PK..........!\.'|
00000010  be 30 61 01 00 00 96 03  00 00 13 00 00 00 5b 43 |.0a...........[C|
00000020  6f 6e 74 65 6e 74 5f 54  79 70 65 73 5d 2e 78 6d |ontent_Types].xm|
00000030  6c b2 b1 af c8 cd 51 28  4b 2d 2a ce cc cf b3 55 |l.....Q(K-*....U|

Preview

XLSX files cannot be shown in a browser. Download the file and open it in an application that reads XLSX, such as Microsoft Excel.

Where 20 MB matters

A 20,971,520-byte file: right at the default attachment limit of Outlook, and just under the 25 MB ceilings of Gmail and GitHub web uploads. These are the default limits a file of this size is useful for testing:

System	Limit	Note
Microsoft Outlook	20 MB of attachments by default for internet mail accounts	This file is right at the limit; add a second attachment and it is exceeded.
Gmail	25 MB per message	Under the limit, although email encoding adds about a third in transit.
GitHub web uploads	25 MiB per file added through the browser	Accepted. Pushing with Git allows larger files.
Cloudflare Pages assets	25 MiB per file	The largest round size that can be served as a static asset.
Amazon API Gateway	10 MB payload	Rejected; the upload has to go directly to object storage.
ASP.NET Core (Kestrel)	About 28.6 MB request body by default	Accepted with room for the multipart overhead.

All 20 MB sample files

Use this file for

Measuring download speed from your own server or CDN
Load-testing importers with many rows
Testing spreadsheet import features

Testing notes for XLSX

A date cell is a number with a format; importers that ignore the format show values such as 45123 instead of a date.
Reading a large workbook with a DOM-style library can use many times the file size in memory. Test with the 5 MB and 10 MB samples and prefer streaming readers.

XLSX format reference

Technical details

File name	sample-xlsx-20mb.xlsx
Format	XLSX (Excel workbook (Office Open XML))
Extension	.xlsx
MIME type	application/vnd.openxmlformats-officedocument.spreadsheetml.sheet
Size	20,971,520 bytes (20 MB)
Kind	Binary
Signature	50 4B 03 04
SHA-256	94b8d14c535362f4a61c91dc2fcbac1ad73d577c15eec9ecb25c00ef9ff88be0
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	Spreadsheets

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-xlsx-20mb.xlsx     # Linux
shasum -a 256 sample-xlsx-20mb.xlsx # macOS

On Windows, run Get-FileHash sample-xlsx-20mb.xlsx -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 20 MB?: Yes. It is 20,971,520 bytes, which is 20 MB in the binary units that operating systems and server limits use (1 KB = 1,024 bytes).
What is inside the 20 MB XLSX file?: One worksheet with a bold, frozen header row and 225,499 rows of fictional orders: text, dates, numbers and a formula in every row. 2,085 bytes of text in the workbook description property bring the file to the exact size.
Do the workbooks contain macros?: No. They are plain .xlsx files with one worksheet, a frozen header row and simple multiplication formulas.

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