JSON Mock Generator
Create repeatable test fixtures from a JSON Schema. Every generated sample is checked against your schema before you can export it.
Load an example or paste your data to begin.
How to use JSON Mock Generator
- Paste a draft-07 schema, including any internal definitions it references.
- Choose 1–1000 samples and a numeric seed.
- Generate and download the validated fixtures, or review a constraint error.
What to expect
The same schema, seed and options produce repeatable fixtures. External references are not fetched. Complex or unsatisfiable constraints may fail generation; the tool reports this instead of offering invalid fixtures. Work can be cancelled, and long-running requests time out.
JSON Mock Generator FAQ
Will generated data always match my schema?
Only validated output is offered for download. If generation cannot satisfy the schema, an error is shown and no result is exported.
Which Schema version is supported?
This generator supports draft-07. Keep references inside the submitted schema; remote schemas and newer drafts are not fetched or silently substituted.
Does this tool upload my data?
No. Your input and generated files are processed on your device. No account is required.