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    ToolnettA RaftApps Project

    Made with by RaftApps

    © 2026 Toolnett. All rights reserved.

    Free Online JSON Data Generator & Generate Mock API Online

    Generate mock API data

    Verified Local Processing (100% Client-Side)

    Your data never touches our servers. All logic executes in your browser sandbox using WebAssembly (WASM). No uploads, no logging, zero data retention.

    Verify in Network Tab
    Offline-Ready Security

    Fake JSON Generator

    Generate custom mock JSON data for your APIs and testing

    Schema Definition

    JSON Output

    // Configure schema and click generate...
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    About Fake JSON Gen

    Generate mock JSON data for APIs online for free. Custom schema support for developers. Professional API testing tool.

    Key Features

    • Highly customizable JSON schema
    • Generates nested objects and arrays
    • Syntax highlighting for results
    • One-click copy for API testing

    How to Use

    1. 1Define your JSON key names and types
    2. 2Specify the number of records to generate
    3. 3Copy the mock JSON data for your application

    Frequently Asked Questions

    Everything you need to know about JSON Data Generator.

    The Best Free Online Mock JSON Generator

    Simulate your backend instantly with our professional JSON data builder. Define your API schema and get structured, realistic data to test your frontend components without waiting for a server.

    Fast API Prototyping

    Our tool supports complex nested objects and arrays, giving you the flexibility to mock any data structure. It's the fastest way to generate JSON online for reliable and thorough application testing.

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