Mock JSON Data Generator
About Mock JSON Data Generator
The mock JSON data generator produces realistic fake data from a simple field spec — names, emails, dates, UUIDs and more. Describe the shape you want once and get an array of populated records to seed a database, drive a demo, or fill out test fixtures.
Generation runs in your browser with no upload and no account. Because the data is synthetic and produced locally, there is nothing sensitive to leak — it is free and unlimited.
It is for developers who need believable placeholder data fast: prototyping a UI against a list, load-testing a form, or writing tests that need a batch of varied records instead of hand-typed samples.
How it works
Writing the field spec
Define an object where each key maps to a data type — such as name, email, date or uuid. The generator reads that spec and produces records matching those field types, so you control exactly which fields appear and what kind of value each holds.
Choosing how many records
Pick the count — 10, 50 or 100 — to generate that many objects in an array. This lets you produce anything from a quick handful for a screenshot to a fuller set for exercising pagination or scrolling.
The generated values
Names, emails and similar fields get plausible, varied values rather than repeated placeholders; UUIDs are unique per record; dates fall in a sensible range. The result is JSON you can paste straight into a fixture or seed script.
Deterministic shape, varied data
Every record follows the same field spec so the shape is consistent and safe to type against, while the values differ between records so lists look realistic and edge cases show up.
Frequently asked questions
What field types can I generate?
Common ones like names, emails, dates and UUIDs driven by your field spec. Define the keys you want and map each to a supported type, and the generator fills them with varied, plausible values.
How many records can I create at once?
Choose 10, 50 or 100 from the count control. Every record follows the same spec, so the batch is consistent in shape but varied in values.
Is the fake data safe to use — does it contain real people?
No. The values are randomly generated placeholders, not real personal data. Everything is produced locally in your browser.
Are the generated UUIDs unique?
Yes. Each record gets its own UUID, so you can use them as distinct identifiers across the generated set.
Is anything uploaded when I generate data?
No. Generation happens entirely client-side, and since the data is synthetic there is nothing sensitive involved either way.