100 MB ICS sample

An ICS file of exactly 104,857,600 bytes. It is a valid iCalendar file file, generated by this site. Compare its checksum and test it with the parser used by your application. Use it wherever you need a 100 MB sample, test or dummy ICS file.

sample-ics-100mb.ics

100 MB104,857,600 bytes

Download 100 MB ICS

Created in your browser and, in browsers that can stream to disk, sent straight to your downloads list; this can take a minute. No sign-up.

Type: text/calendar
SHA-256: c506b2765f8e625a23c6a6499af1fb4657911cb3394f710376dda11fe99a8bc3
Delivery: Created in your browser from static generator assets (how it works).

What is in this file

A VCALENDAR with 305,816 one-hour events, each with a UID, start and end in UTC, a summary, a folded description and an escaped location. Extension properties (X-FIXTURE-PAD), which calendar programs ignore, bring the file to the exact size.

Events	305,816
Version	iCalendar 2.0 (RFC 5545)
Time zone	UTC
Line endings	CRLF, folded at 75 octets
Encoding	UTF-8 (ASCII characters only)

How the file begins

The opening lines of sample-ics-100mb.ics, exactly as they appear in the file.

00000000  42 45 47 49 4e 3a 56 43  41 4c 45 4e 44 41 52 0d |BEGIN:VCALENDAR.|
00000010  0a 56 45 52 53 49 4f 4e  3a 32 2e 30 0d 0a 50 52 |.VERSION:2.0..PR|
00000020  4f 44 49 44 3a 2d 2f 2f  53 61 6d 70 6c 65 54 65 |ODID:-//SampleTe|
00000030  73 74 46 69 6c 65 73 2f  2f 53 61 6d 70 6c 65 20 |stFiles//Sample |

Preview

Creates the file in your browser and shows the first 64 KB of it.

Where 100 MB matters

A 104,857,600-byte file: the request-body limit of Cloudflare's Free and Pro plans, and the size above which GitHub rejects a file outright.

All 100 MB sample files

Use this file for

Finding the first upload limit in a new stack
Testing invitation processing
Testing calendar import and subscription

Testing notes for ICS

Time zones and recurrence rules are where calendar software fails. The samples use UTC and non-recurring events, so they work as a known-good baseline.
Importing the same UID twice should update an event, not duplicate it.

ICS format reference

Technical details

File name	sample-ics-100mb.ics
Format	ICS (iCalendar file)
Extension	.ics
MIME type	text/calendar
Size	104,857,600 bytes (100 MB)
Kind	Text
SHA-256	c506b2765f8e625a23c6a6499af1fb4657911cb3394f710376dda11fe99a8bc3
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	Available on this page
Source	Generated in your browser by this site's generator; not copied from elsewhere
Licence	Free to use, modify and redistribute (terms)
Category	Email & Calendar

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-ics-100mb.ics     # Linux
shasum -a 256 sample-ics-100mb.ics # macOS

On Windows, run Get-FileHash sample-ics-100mb.ics -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 100 MB?: Yes. It is 104,857,600 bytes, which is 100 MB in the binary units that operating systems and server limits use (1 KB = 1,024 bytes).
What is inside the 100 MB ICS file?: A VCALENDAR with 305,816 one-hour events, each with a UID, start and end in UTC, a summary, a folded description and an escaped location. Extension properties (X-FIXTURE-PAD), which calendar programs ignore, bring the file to the exact size.
Do the events repeat?: No. Each event is a single one-hour meeting in UTC with its own UID.

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