Example input and settings
{"id":"{{sequence}}","profile":{"age":"{{integer:18:18}}"}} · JSON · 2Developer · DEV-12Submit an issue
Fake data generator
Generate test data in batches from custom JSON structures and field rules. Preview, copy and download generated data as JSON, JSONL or CSV.
Includes user, product and order examples. Supports sequences, UUIDs, names, emails, cities, numeric ranges, booleans, dates, choices and random text, with type preservation and text interpolation.
Record structure
Generated data
Data updates automatically when the structure or count changes.
CSV uses top-level fields as columns; nested objects and arrays are stored as JSON in a cell. Dates use UTC. Generate 1–1,000 fictional records, with an 8 MB output limit.
Generation rules
| Placeholder | Value |
|---|---|
{{sequence:1:1}} | Sequence; optional start and step |
{{uuid}} | Random UUID |
{{name}} | Full name |
{{firstName}} / {{lastName}} | First name / last name |
{{email}} | Test email at example.com |
{{city}} | City |
{{boolean}} | Boolean true or false |
{{integer:18:65}} | Integer, inclusive bounds |
{{float:0:999:2}} | Number, 2 decimal places |
{{date:2020-01-01:2030-12-31}} | Date, inclusive bounds (UTC) |
{{datetime}} | Timestamp in the date range (UTC) |
{{pick:active|paused}} | One string from a list |
{{text:12}} | 12 alphanumeric characters (1–256) |
{{word}} | Sample word |
Work with configuration and network data
Define one record as a JSON object in the code editor, with custom fields, nested objects and arrays, or load a user, product or order example. Use {{sequence}}, {{integer:18:65}} and {{pick:active|paused}}; whole placeholders retain numeric and boolean types. Generate 1–1,000 records and copy or download JSON, JSONL or CSV. Switching formats reuses the same records; CSV stores nested values as JSON in a cell. Arrays keep their template length, dates use UTC and output is limited to 8 MB.
Check the input format and options with this example before using your own data. Random values, file sizes and presentation vary with the input and settings.
What to check in the result
[{"id":1,"profile":{"age":18}},{"id":2,"profile":{"age":18}}]