Mock JSON Data Generator

How to use

1. Pick a row count — Set how many fake user records you need (1–500).
2. Generate — Click Generate to produce a fresh JSON array.
3. Copy or download — Use the array directly in your tests, stubs, or seed scripts.

Why Mock Data Matters

Realistic mock data is the difference between a UI that looks polished in screenshots and one that breaks the moment a real user logs in. Long names, weird emails, edge-case ages — fake records with the right shape catch layout, sorting, and validation bugs before QA ever opens the build.

What This Generator Produces

A JSON array of user-like objects with stable, predictable keys. Every record has a UUID, a plausible name, an email, an age, a city, a role drawn from common access tiers, an active flag, and an ISO createdAt timestamp. The shape covers the majority of CRUD UIs without further tweaking.

How to Use It in Tests

Generate 10–50 records and commit the JSON into your test fixtures folder. Stable fixtures make snapshot tests deterministic. For network mocking, wire it into MSW (rest.get('/api/users', () => res(ctx.json(fixture)))) or json-server (npx json-server mock-data.json) for an instant REST endpoint.

When to Switch to a Library

This page is for quick, one-off needs — a Figma screenshot, an empty-state demo, a single Jest fixture. If you need locale-specific data, custom schemas, foreign keys between tables, or reproducible seeds, switch to Faker.js, Chance.js, or @snaplet/seed inside your project. They give you full control and run in your build, not the browser.

Privacy Note

Nothing here is sent over the network. The dictionaries (names, cities, domains) live in this page's source code. The "emails" use safe demo TLDs that aren't backed by real mail servers. Generate freely.

Frequently asked questions

What fields does each record include?

Each mock user has: id (UUID v4), name, email, age (18–67), city, role (admin/editor/viewer/owner/guest), active (boolean), and an ISO createdAt timestamp within the last two years. A realistic shape for most CRUD UIs.

Is any of this data real?

No. Names, emails and cities are randomly assembled from a small fixed dictionary inside this page. Any resemblance to a real person is coincidental. Never use these emails to send actual messages.

Can I generate more than 500 records?

The UI caps at 500 to keep the browser responsive. For larger fixtures, generate twice and concatenate — or open the page source and call buildUser() in a loop in DevTools.

Is this safe for production seed data?

It's fine as a starting point for development databases. For production-like load tests, prefer libraries like Faker.js in your build pipeline so you can deterministically reseed with a known random seed.

Does this leave my browser?

No. The generator uses crypto.randomUUID() and Math.random() in your browser. No data is sent to any server.

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