Mock JSON Data Generator
This mock JSON data generator lets you define a schema of named fields, pick a v
This mock JSON data generator lets you define a schema of named fields, pick a v
How to use Mock JSON Data Generator
- Add a field for each JSON key and choose its value type from the dropdown.
- Set how many records to generate and pick JSON array or NDJSON output.
- Press Regenerate, then copy the result or download it as a file.
About Mock JSON Data Generator
This mock JSON data generator lets you define a schema of named fields, pick a value type for each (names, emails, UUIDs, dates, integers, prices, booleans, enums, lorem sentences and more), and generate up to 1,000 realistic sample records at once. You can output a standard JSON array, wrap it under a root key like "data", or emit NDJSON with one object per line for tools that expect line-delimited records. Copy the result or download it as a .json or .ndjson file.
Values are produced with your browser's built-in random source and small curated word lists, so the data looks realistic (plausible names, email addresses, ISO dates) without being real. The auto-increment ID field gives you predictable primary keys, while every other field is randomized each time you press Regenerate. It is meant for seeding databases, mocking API responses, load-testing UI components and building demos, not for statistical accuracy or cryptographic randomness.
Everything runs entirely in your browser. No schema, field name or generated record is uploaded to a server, and there is no account or API key. Nothing leaves your device, so it is safe to use for internal projects and offline work.
Frequently asked questions
- How do I generate mock JSON data?
- Add a row for each field you want, type a field name and choose a value type from the dropdown. Set how many records you need, then press Regenerate to build the JSON. Copy it or download it as a file.
- Is the generated data real or does it come from a real database?
- No. Every value is randomly generated in your browser from small built-in word lists. Names, emails, phone numbers and dates are plausible but entirely fake, so they are safe for testing without exposing anyone's real information.
- Is my schema or data sent to any server?
- No. The tool is 100% client-side. Your field names, types and the generated records never leave your browser, and there is no sign-up or API key required.
- What output formats and limits are supported?
- You can output a pretty-printed JSON array, wrap it under an optional root key, or emit NDJSON (one JSON object per line). You can generate between 1 and 1,000 records per run to keep the browser responsive.
- What field types are available?
- Auto-increment ID, UUID, first/last/full name, email, username, phone, city, country, company, product name, URL, integer, decimal price, boolean, status enum, date, ISO datetime, lorem sentence and hex color.
- Why does the data change every time?
- Each Regenerate click produces a fresh random set so you can get varied test data. The auto-increment ID field stays predictable (1, 2, 3...), while all other fields are re-randomized.