01 / JSON / json-generator
JSON Generator
Build a nested schema and generate mock JSON records.
How to use
- 01Set how many records you need (up to 10,000).
- 02Define your schema: a field name and a data type per row.
- 03Choose Object or Array as a type to nest structures as deep as you need, then add child fields.
- 04Optionally set a root key so the output is wrapped, e.g. { "users": [ … ] }.
- 05Press Generate to build the mock dataset.
- 06Copy the JSON, or download it as JSON or CSV.
What is this tool?
The JSON generator is a small schema editor that produces realistic-looking but entirely fictional records for testing. It supports 20 data types including UUID, email, name, dates, addresses and numbers, plus nested objects and arrays for multi-level payloads and a custom root key. It never generates real personal data or credentials.
Common use cases
- Seeding a local database with sample rows
- Building API mocks and contract test fixtures
- Load-testing endpoints with bulk payloads
- Populating UI prototypes with plausible data
FAQ
How many records can I generate?
Up to 10,000 records per run to keep the browser responsive.
Is the data real?
No. All values are synthetic sample data intended for testing only.
Can I generate nested JSON?
Yes. Set a field type to Object or Array and add child fields to nest as deeply as you need.
Can I name the root of the document?
Yes. Set a root key and the array is wrapped in an object under that name.
Can I export CSV?
Yes, both JSON and CSV downloads are supported; nested fields are flattened into dot-notation columns.
Does this call a server?
No. Generation runs entirely in your browser.