Generate a large JSON test file
Builds a file of any size in your browser and downloads it — nothing is generated on a server, so you can make a 100 MB file without a 100 MB download. Use it to try the streaming formatter on the formatter page.
Build a file
How to read the results
Drop the generated file onto the formatter. Files above 4 MB switch
to streaming mode automatically: the bytes are read with file.stream() inside a Web Worker
and fed to a byte-level scanner, so the document is never turned into a JavaScript string and never
parsed into an object. Memory stays flat no matter how big the file is.
On an invalid file, note two things: the exact line and column, and how much of the
file was read before scanning stopped. A tool built on JSON.parse has to load the whole
document into memory before it can report anything at all.
Honest limits. Validating, formatting and minifying stream, and are capped at 100 MB. The JSONPath tester, schema validator and diff need the parsed values in memory and cap near 20 MB — the formatter tells you when you have crossed that line instead of freezing.