How to use Synthetic Test Dataset Generator
- Enter the row count, seed and supported column schema.
- Choose CSV, JSON or SQL fixture output.
- Review the synthetic rows before using them in a test environment.
Example: Synthetic Test Dataset Generator
100 rows, seed 42, with an id and a synthetic label column.
You add
Rows: 100
Repeatable seed: 42
Sample columns (JSON): [{"name":"sample_id","type":"id"},{"name":"label","type":"label"},{"name":"amount","type":"decimal","min":0,"max":100,"precision":2},{"name":"category","type":"category","values":["Sample A","Sample B","Sample C"]},{"name":"date","type":"date","start":"2026-01-01","end":"2026-12-31"}]
SQL table name: synthetic_samples
You get
Generated 100 explicitly synthetic rows with seed 42. Sample rows: FAKE-000001 | Sample 000001 | 60.11 | Sample B | 2026-11-08; FAKE-000002 | Sample 000002 | 66.98 | Sample A | 2026-07-12.
Options
- Repeatable seed
- Keep the seed, schema and row count together when reproducing a fixture. The seed is for repeatable test data and must not be used to generate passwords or security tokens.
- Sample columns
- Choose the supported field types and their bounds. Category values come from your entered list, and labels describe fake samples rather than verified people.
Supported inputs and limits
Up to 10,000 rows, 20 columns and 8 MiB output. Supported id, label, integer, decimal, date, category and boolean fields only. Labels are synthetic examples, not real people or validated locale identities. SQL is a downloadable fixture, not a database import or execution.
Where your input is processed
This tool processes your input in this browser. Your text and files are not uploaded to UseFreeTools. Check this tool's limits for anything it may save on your device.
Use a fixture that answers your test question
A repeatable dataset can help reproduce an import or formatting problem. It does not measure real-world distributions or replace representative production cases. Check the downloaded CSV, JSON or SQL and keep it clearly labelled synthetic. SQL output is a file for review; generating it does not create a table or insert rows into a database.
Questions about Synthetic Test Dataset Generator
Are the generated identities real?
No. Labels are explicitly synthetic and do not describe real people.
Can I reproduce a fixture?
Yes. Keep the same supported schema, row count and seed.
Will SQL be applied to a database?
No. It is exported as text for your review.