Data · JSON
A 5 MB JSON file, on demand.
Exactly 5,242,880 bytes of a valid JSON document with a records array, built on your machine the moment you press the button.
5,242,880 bytes, exactly.
Every byte above the 60 bytes structural minimum goes into a trailing string field, so the document still parses, which is why this file still behaves like one a real user would send.
Unit convention
5 MB on this page means exactly 5,242,880 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 2,913 pages of typed text, 5 minutes of 128 kbps audio, 30 seconds of CD-quality audio, 2.1 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 JSON sizes
Default limits start biting here: PHP ships with a 2 MB cap, and many form builders stop at 5 MB.
Questions.
Is this 5 MB JSON file valid?
Yes. It is a valid JSON document with a records array. The extra bytes sit in a trailing string field, so the document still parses, so it opens in jq, browser devtools, Python's json module and Node's JSON.parse.
Does 5 MB mean 5,242,880 bytes?
On this page, yes — 5 MB uses the binary (MiB) convention, so the file is exactly 5,242,880 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 5 MB file used for?
Default limits start biting here: PHP ships with a 2 MB cap, and many form builders stop at 5 MB. For JSON specifically, the usual job is testing API payload limits and request body caps.
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.