Mocksy - API Server & Mock

Offline dev server for testing

Only for Mac

Free

Mac

Mocksy is a powerful macOS tool for creating mock API endpoints, previewing JSON responses, and inspecting every request in real time. Whether you’re building an iOS, macOS, or web app, Mocksy helps you test faster without relying on live backend services. Build fully customizable local servers, craft flexible responses, and instantly verify how your app communicates with APIs. Mocksy is designed for developers who want a smooth, reliable workflow during prototyping, testing, and debugging. Key Features Create custom mock endpoints with JSON, headers, and status codes Local server engine that runs instantly—no setup required Live request inspector to monitor calls and debug traffic Preview responses exactly as clients receive them Organize multiple endpoints for different testing scenarios Lightweight, fast, and built for macOS Mocksy removes backend blockers and gives you complete control over your testing environment. Perfect for mobile developers, web developers, and anyone building on APIs.

Ratings & Reviews

  • This app hasn’t received enough ratings or reviews to display an overview.

### Added - Import collections from Postman (v2.1.0 format) - Import collections from Insomnia - Import collections from Mockoon - File menu with Import commands - Response Headers section in endpoint detail view - Default Headers section in server settings with CORS quick-fill - Reusable HeadersEditorView component for key-value header editing - Endpoint folders for better organization ### Changed - Port can now be changed in server settings

Version 1.3.0

The developer, Justas Zaltauskas, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .

  • Data Not Linked to You

    The following data may be collected but it is not linked to your identity:

    • Usage Data
    • Diagnostics

Privacy practices may vary, for example, based on the features you use or your age. Learn More

Accessibility

The developer has not yet indicated which accessibility features this app supports. Learn More

Information

Seller
  • Justas Zaltauskas
Size
  • 16.5 MB
Category
  • Developer Tools
Compatibility
Requires macOS 15.0 or later.
  • Mac
    Requires macOS 15.0 or later.
Languages
  • English
Age Rating
4+
Copyright
  • © 2026 Justas Zaltauskas
  • Privacy Policy

    • More by Justas Zaltauskas