Dummy JSON Api Generator
Fast, accurate and free online dummy json api generator tool running directly in your browser.
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1Enter data
Enter content, paste text or load a file from disk. -
2Click the button
The tool will immediately process your data in the browser. -
3Get the result
Copy the finished text or save the file to your device.
return "Result ready in 0.1s";
}
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Other tools you may find usefulTest JSON API generator – mock REST data without backend
When frontend prototyping, the backend often does not exist yet. The tool generates realistic JSON data for typical REST endpoints: lists of users, products, orders, articles. You can configure the schema, number of records and field types - the result is a ready JSON file or response mock.
Available data schemas
Users: id, name, email, avatar, role, createdAt. Products: id, title, price, category, stock, rating. Orders: id, userId, items[], total, status, date. Articles/posts: id, title, body, author, tags[], publishedAt. Your own schema: you define fields and types (string, number, boolean, date, uuid, enum).
Types of generated values
Realistic fake data: names (Faker.js locale pl), email addresses in [email protected] format, UUID v4, ISO 8601 dates, prices with cents, numerical ranges (min/max), lorem ipsum (PL/EN), HEX colors, GPS coordinates (PL range), phone numbers +48.
Output formats
JSON array: [{...},{...}]. Paginated: {data:[...], total:N, page:1, per_page:10}. Nested (relationships): user.orders[]. JSON Lines (NDJSON): each record on a separate line - good for logs and streaming. TypeScript interfaces: automatically generated type based on the schema.
Integration with dev tools
JSON Server: REST server based on a JSON file (npm install -g json-server). MSW (Mock Service Worker): interprets requests in the browser. Postman / Insomnia: import as collection. Storybook: data as props for stories. Vitest/Jest: Import JSON as test data.
FAQ
How is it different from JSONPlaceholder?
JSONPlaceholder (jsonplaceholder.typicode.com) is a public server with ready-made endpoints (but constant data). This tool: generates new data locally, supports its own schemas, does not require the Internet, data can be downloaded and used offline.
How to use mock JSON with React?
import data from "./users.json". Or: const [users, setUsers] = useState([]); useEffect(()=>fetch("/api/users").then(r=>r.json()).then(setUsers),[]). From MSW: the server captures /api/users and returns the generated JSON.
How many records can be generated?
The tool generates up to 10,000 records in the browser (JavaScript). For larger datasets: download and use node-generate-data or Faker.js in your Node script.
Is the data random on each refresh?
Default yes. You can set a seed for repeatable data - useful when you want the same data in tests. The seed determines the order and values of the pseudorandom generator (Mersenne Twister).
How to generate nested relations (user → orders)?
In the interface, select the "Users with Orders" scheme. Or manually: define the orders field as array[Order]. The tool generates consistent relationships (userId in orders matches user IDs).
Related tools: JSON validator, JSON to CSV converter and cURL to Fetch API converter.