Moqyy — API Mocking & Fetch/XHR Interceptor

Mock APIs, intercept fetch/XHR requests, and test frontend apps without backend. Built for frontend developers and QA testers.

Moqyy is the easiest way for frontend developers and QA testers to mock API responses and intercept network requests inside the browser. Mock APIs instantly, intercept **fetch** and **XMLHttpRequest (XHR)** calls, and test your frontend without waiting for backend endpoints. Moqyy is lightweight, fast, and built specifically for modern frontend workflows (React, Vue, Next.js, Angular). Key features • Intercept **fetch** and **XHR** calls. • Create API mock rules in one click. • Auto-fill request/response patterns and templates. • Save mock rules locally and import/export JSON. • Enable/Disable mocks globally or per-rule. • Capture real responses to use as a mock (Auto-capture). • Test different server responses (200, 400, 500, custom JSON). • Lightweight extension that won’t clutter your devtools. Who should use Moqyy • Frontend developers building UI without backend readiness. • QA teams testing client behavior for edge/backend error states. • Engineers who need fast, local API mocks without complex setup. Quick start 1. Install the extension. 2. Open the Network tab in Moqyy and trigger a fetch/XHR from your app. 3. Click the “+” next to a request to create a mock. 4. Edit the mock response and enable it — refresh your app and see the mocked response in action. Why Moqyy vs other tools • Focused on **API mocking** for frontend workflows (not a general network toolbox). • Simpler onboarding and a modern UI that developers prefer. • Built for speed — create useful mocks in under 30 seconds. If you find issues or want features, use the in-extension Feedback button — we read every message.