System · BAT
A 100 MB BAT file, on demand.
Exactly 104,857,600 bytes of a Windows batch script with a real @echo off header, built on your machine the moment you press the button.
104,857,600 bytes, exactly.
Every byte above the 111 bytes structural minimum goes into unreachable text after a goto :eof, which cmd.exe never parses, which is why this file still behaves like one a real user would send.
Unit convention
100 MB on this page means exactly 104,857,600 bytes, using the binary (MiB) convention some systems label "MB" for short. 1 MB in the strict decimal sense is 1,000,000 bytes; 1 MiB is 1,048,576 bytes — the readout above always shows the exact count either way.
Approximate size equivalents
Roughly 58,254 pages of typed text, 109 minutes of 128 kbps audio, 10 minutes of CD-quality audio, 42 photos from a 12 MP camera. These figures compare file size only — the generated file does not contain this text, audio or image content.
Accepted by
Cloudflare Free proxy body, GitHub repository file, Slack free workspace file — all publish a limit at or above this size, based on commonly cited figures that can vary by plan and change over time.
Rejected by
Gmail attachment, Outlook.com attachment, Discord free attachment — this exceeds their commonly cited limit, which makes it a useful negative test. Published limits can vary by plan and change over time.
Other BAT sizes
Files this large exercise multipart and chunked upload paths rather than a single request, which is usually where the bugs are.
100 MB in other system formats
Questions.
Is this 100 MB BAT file valid?
Yes. It is a Windows batch script with a real @echo off header. The extra bytes sit in unreachable text after a goto :eof, which cmd.exe never parses, so it opens in Notepad, VS Code and cmd.exe.
Does 100 MB mean 104,857,600 bytes?
On this page, yes — 100 MB uses the binary (MiB) convention, so the file is exactly 104,857,600 bytes. 1 MB in the strict decimal sense would be a different, smaller byte count. Upload validators may use either convention, so the exact byte count is always shown to remove any ambiguity.
What is a 100 MB file used for?
Files this large exercise multipart and chunked upload paths rather than a single request, which is usually where the bugs are. For BAT specifically, the usual job is testing script upload handling and text-file size limits.
Where is the file downloaded from?
Nowhere. It is assembled in a Web Worker on your own device and handed to the browser as a Blob, so nothing is uploaded, fetched or stored.