Offline API mock and patch engine for browser requests.
Users
10
0 in 30 days
Rating
5.0 / 5
unchanged in 30 days
Ratings
2
0 in 30 days
Store rank
#192K
#160K among extensions
Version
1.1.0
updated 25 Feb 2026
Users
monthly, 8 months
Latest, 16 Oct 2026:10 usersMove the mouse over the chart for any month
Ratings count
monthly, 8 months
Latest, 16 Oct 2026:2 ratingsMove the mouse over the chart for any month
The Chrome Web Store rounds user counts down to the leading digit, so the user line moves in steps. The ratings count is exact and is the better signal of real adoption.
About Echo - API Mock & Patch Engine
Echo - API Mock & Patch Engine
Overview
Echo is a powerful developer tool designed to streamline frontend development and testing by giving you complete control over network requests. Intercept `fetch` and `XMLHttpRequest` calls directly in the browser to mock APIs, simulate errors, and test edge cases without modifying your application code.
Key Features
1. Request Interception: Capture and control HTTP requests on any page.
2. Mock Responses: Serve custom JSON or text responses instantly.
3. Live Patching: Modify request/response headers, bodies, or status codes on the fly.
4. Network Simulation: Add configurable delays to test loading states and race conditions.
5. Advanced Matching: Target specific requests using URL patterns (exact, contains, regex) and HTTP methods.
6. Offline Development: Continue working even when backend services are down.
7. User-Friendly Interface: Modern UI with a powerful JSON editor and drag-and-drop rule management.
Why Install Echo?
*Boost Productivity: Stop waiting for backend endpoints to be ready. Mock them in seconds.
*Debug Faster: Reproduce hard-to-find bugs by forcing specific API responses or errors (e.g., 500, 404).
*Test Safely: Experiment with API changes safely in your browser without risking production data.
Perfect for frontend developers, QA engineers, and anyone building web applications.
Growth
Window
Users
Change
Ratings
Rating
7 days
−1
−9.1%
0
0.00
30 days
0
+0.0%
0
0.00
6 months
+7
+233.3%
0
0.00
Chrome Web Store search rankings
Where Echo - API Mock & Patch Engine appears when people search the store, with the 30 day change