Images · WebP
A 9 MB WebP file, on demand.
Exactly 9,437,184 bytes of a WebP image encoded by your browser, built on your machine the moment you press the button.
9,437,184 bytes, exactly.
Every byte above the 1,309 bytes structural minimum goes into a custom RIFF chunk, with the container size field corrected afterwards, which is why this file still behaves like one a real user would send.
Unit convention
9 MB on this page means exactly 9,437,184 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 5,243 pages of typed text, 10 minutes of 128 kbps audio, 53 seconds of CD-quality audio, 3.8 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
Discord free attachment, AWS API Gateway payload, Outlook.com attachment — 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
PHP default upload_max_filesize — this exceeds their commonly cited limit, which makes it a useful negative test. Published limits can vary by plan and change over time.
Other WebP sizes
Mail servers and chat apps draw the line in this band — Gmail attachments stop at 25 MB, and plenty of APIs cap request bodies alongside them.
Questions.
Is this 9 MB WebP file valid?
Yes. It is a WebP image encoded by your browser. The extra bytes sit in a custom RIFF chunk, with the container size field corrected afterwards, so it opens in modern browsers, Photoshop 23+ and libwebp tools.
Does 9 MB mean 9,437,184 bytes?
On this page, yes — 9 MB uses the binary (MiB) convention, so the file is exactly 9,437,184 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 9 MB file used for?
Mail servers and chat apps draw the line in this band — Gmail attachments stop at 25 MB, and plenty of APIs cap request bodies alongside them. For WebP specifically, the usual job is testing next-gen image delivery and format negotiation.
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.