Online JSON Generator: customize rows and fields to instantly generate sample JSON array data. Ideal for API testing, mock data, and frontend development. All processing is done locally.
TL;DR: Free online JSON generator. Produce sample JSON arrays in one click with custom row and field counts and diversified value types. Ideal for API testing, mock data, and frontend development. Local processing.
This tool runs entirely in your browser. Open DevTools → Network panel and search your input — it appears in no request.
Next steps
Usage Guide
Demos, placeholders, and test schemas often need plausible JSON. Generate a random array of objects by row/column count — locally random, nothing uploads.
1. Generate JSON
Keys/values are generic randoms, not business-meaningful. For realistic names/phones/emails, use mock-data-generator.
- Set row (record) and column (field) counts.
- Generate an array of objects.
- Copy or download for mocks, prototypes, or demos.
2. Which generator when
Output changes every run; pin samples when docs or tests need determinism.
- Structure placeholder with arbitrary fields: fastest here.
- Realistic typed fields (emails, phones, dates): mock-data-generator.
- Deterministic fixtures: hard-code JSON or seed — random values break golden tests.
3. Follow-ups
Run json-sorter afterward for stable diffs.
- Validate shape with json-schema-validator.
- Generate types via json-to-typescript / go / java.
- Pretty-print with json-formatter before docs.
FAQ
Completely free with no registration. Sample data is generated locally in your browser with no server involved.
Yes. Both row and field counts are customizable, with field names and value types diversified automatically.
API integration, frontend development, and unit testing wherever mock data is needed — generate, copy, and go.
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