generate fake JSON data
Build the columns in the generator and pick JSON or NDJSON as the output: each row becomes an object with the right types, and the same seed repeats the whole file. Below is what the tool writes and why each choice matters once you use the file.
Number, string, boolean, decimal and null keep their type.
The escape keeps the NDJSON record on a single line.
With indentation off, one object per line.
The column name becomes the key unchanged.
Still valid JSON.
There is no fixed row limit beyond a safety ceiling of 100 million per table, which only guards against typos. The real limit is your device's memory and disk: data is generated in blocks of 2,000 rows and the browser builds the file piece by piece. In Chromium browsers, from 100,000 rows the tool asks for a location to write straight to disk, without gathering the whole file in memory. The estimated file size appears below the preview, computed from the sample, and you can cancel a long run at any time.
A JSON array is a single document: it is only valid after the closing bracket, so a program has to read everything before using the first record. NDJSON has one document per line, which allows stream processing, cutting the file with head, joining files with cat and loading billions of lines without exhausting memory. For small fixtures the array is more comfortable; for volume, prefer NDJSON.
Documents are text: a CPF or ZIP code can start with a zero, and converting it to a number would erase that zero. Only numeric column types (sequence, integer, decimal, age, price) come out unquoted.
Yes. Generate with a fixed seed, version the file or, better, keep the saved schema and the seed in the repository and generate again when needed: the result is identical on any machine. Use example.com emails and fictitious documents, which do not point to real people.
Fictitious data for testing. Documents only have the correct format and check digits, belong to no one and must not be used for fraud or to bypass verification. Cards and IBANs move no money.