Description
API Mocker - The Ultimate API Mocking & Testing Tool
Short Description
Intercept, modify, and mock HTTP requests directly in your browser. No backend required.
Long Description
API Mocker is a powerful developer tool that gives you complete control over your browser's network traffic. Whether you're a frontend developer waiting for backend APIs, a QA engineer testing edge cases, or a designer tweaking UI states, API Mocker streamlines your workflow by allowing you to simulate any API response instantly.
Why You Should Install It:
π Zero Backend Dependency: Start building your frontend immediately. Define API rules and get JSON responses without writing a single line of backend code.
β‘ Accelerate Development: Stop waiting for API deployment. Mock missing endpoints and proceed with your UI implementation.
π§ͺ Test Edge Cases Easily: How does your app handle a 500 error? Or a 404? Or a slow network? Simulate these scenarios with a single click to ensure your app is robust.
Key Features:
Intercept & Modify: Automatically capture XHR and Fetch requests matching your custom URL patterns.
Dynamic Rule Management: Create, edit, and toggle mocking rules on the fly with a clean, intuitive interface.
Flexible Matching: Support for exact URL matching and wildcard patterns (e.g., /api/users/*).
Full Response Control: Customize HTTP status codes (200, 400, 500, etc.), response headers, and response bodies (JSON, Text, XML).
Network Simulation: Add artificial delays to simulate slow network connections and loading states.
Visual Notifications: Get real-time feedback when a request is intercepted and mocked.
How It Works:
Open the API Mocker interface.
Add a new rule (e.g., Match https://api.example.com/users).
Define the response you want (Status 200, Body: [{ "id": 1, "name": "Test User" }]).
Browse your site. When the app requests that URL, API Mocker intercepts it and serves your defined response instantly.
Perfect for: Frontend Developers, QA Testers, and Full Stack Engineers looking for a lightweight, browser-based mocking solution.
Privacy-First: API Mocker runs entirely within your browser. No data is sent to external servers.
Reviews
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Permissions (1)
Permissions
storageβΉ Can store data locally in your browser
Details
| Version | 1.0.0 |
| Updated | Dec 16, 2025 |
| Size | 61.29KiB |
| First Seen | Mar 30, 2026 |
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