Shape the network.
Mock APIs instantly.
A powerful developer tool to intercept browser requests. Mock responses, simulate errors, and alter headers directly in Chrome without touching backend code.
ECHOLOGIN
POST contains "/login"
Granular Network Control
Build, patch, and simulate robust frontend experiences. Directly inside your browser.
Intelligent Routing
Target requests using precise configurations: exact URL mapping, fuzzy text containing, or advanced regex patterns.
Request Patching
Dynamically modify outbound Request Headers before they hit the server. Inject auth tokens on the fly.
Status Overrides
Force 500s or 404s without bringing down your actual backend to test UI error boundaries.
Body Strategy
Full control over text/JSON response payloads. Replace entire responses to mock endpoints that don't exist yet.
Simulated Delays
Add arbitrary millisecond (e.g., 5000ms) delays to specific routes to test global loaders and race conditions.
Designed for Developers
Unblock Frontend Dev
Don't wait for backend schemas. Mock the exact JSON shapes you need right now using the built-in editor.
Simulate Real UI States
Combine request delays with destructive status overrides to perfect your loading skeletons and error toasts.
Zero Configuration
No CLI proxies, no codebase changes, no environment variable dancing. It intercepts natively at the browser level.
The Echo Workflow
- 1
Define the Match
Choose GET/POST and set the URL rule (e.g. contains '/login').
- 2
Set the Override
Apply a 2000ms delay and paste your mocked JSON response.
- 3
Activate & Test
Toggle the rule on. Intercept fetch calls transparently.