Modify & Mock
API Responses
in Real-Time
- Validate edge cases
- Stress-test applications
- Simulate backend responses
- Bypass backend complexities
- Mock Third-Party API Responses
Trusted by 200k+ developers at →
Your Development Companion
Gain comprehensive control over API responses for testing edge cases and accelerating frontend development.
Supports APIs triggered as XHR or fetch
Gain control over API responses triggered by XHR/Fetch requests. Eliminate the need for hardcoding in the codebase, and streamline your development workflow.
Test for Edge/Corner Cases
Simulate Errors
Intentionally trigger specific error conditions within your codebase by altering API responses — test error pathways thoroughly without backend changes e.g. Simulate 404 on an API
Serve Without Server:
At times, you may need to modify responses without triggering server requests. In such cases, this feature provides a solution, allowing you to make alterations without engaging the server directly
Async /Await Support
When faced with lengthy API calls or the need to manage multiple requests simultaneously, using an asynchronous approach with Async/Await can significantly improve efficiency
Build frontend when the backend isn’t ready
(Mock/Sub API Responses)
Use the Modify Response rule to create mock APIs with custom responses and status codes. Easily disable these mocks when actual APIs become available.
GraphQL Support
GraphQL’s single-endpoint design can hinder targeted API modification. Requestly solves this with operation name filters, enabling precise response manipulation in GraphQL environments – just as you’d expect with REST APIs.
Collaboration & 1-Click Sharing
Promote consistency and accelerate development by sharing Requestly rules within your team. Choose between shared workspaces for real-time collaboration or targeted sharing with individual members.
Dynamic Response Generation
Generate API responses to your exact needs. Use JavaScript code to modify responses based on request headers, request body, URL, or original response. Perfect for complex testing scenarios or adapting API behavior without backend changes.
More HTTP Request & Response Manipulation Rules
These HTTP Rules designed for all your local development and testing needs.
Redirect Rule
Redirect a matching pattern to another URL.
Cancel Rule
Block URLs by specifying keywords or complete URL.
Replace String
Replace part of URL like hostname, query values.
Modify Headers
Modify HTTP request & response headers.
Query Params
Add or Remove Query Parameters
Insert Script
Inject Custom JS & CSS on any website(s).
Delay Network
Simulate delay in response of API calls.
Modify Request Body
Modify body of POST requests.
Popular Case Studies
Learn from real-world examples, See how others integrate Requestly into their workflows by exploring our case studies.
Requestly Highlights
A comprehensive debugging suite with thoughtfully designed features for front-end developers.
For the developers, by the developers ❤️
Just loved the way Requestly saved several person hours for our dev team by allowing us to redirect and intercept requests. The simple yet efficient rules allowed us to seamlessly redirect requests from a single staging front-end server to local backend servers. This meant that our devs didn’t need to build or run the front-end server locally when focusing on backend tasks.
We are using this extension in my current company as frontend developers to modify API responses and it works very very well. Highly recommend it.
Requestly’s browser extension is remarkably easy to use. As a full-stack developer, I often need to test data-intensive UI for edge cases and performance. Using Requestly I can do it very easily by mocking network requests, without needing code changes or database seeding.
Great tool for frontend developers and QA tester for API response, redirects, mock data and much more. Requestly removes the dependency on waiting for backend API’s. Really useful to have in your frontend development environment.
Requestly is awesome. I used to use Charles proxy in my day-to-day work but it always messed with my wifi. I haven’t had any issues with Requestly. Requestly’s UI is an amazing tool and great to work in.
Requestly not just made it easier for us to develop, test & debug our code on our customer sites but also helped us do engaging product demos to our prospective clients.
I’m a big fan of Requestly, and use it on a daily basis as a QA Engineer. It removes the need to use Charles Proxy often, which is always nice. I can just use Requestly directly in Chrome
Awesome tool. I use it almost daily for my projects to modify request body, headers, etc. Would recommend it to every frontend developer out there. Thank me later 🙂 (Case Study)
This is by far the best tool for managing request headers! Plus the developers are very active meaning you’ll get help if you’re ever stuck or need help solving a problem. I use it daily and couldn’t be happier.
App works as expected! Ran into some small issues while creating the rules but the support team was able to help and overcome those.
Requestly is user-friendly, brilliant and easy-to-use. I use it on an daily basis and it makes my work easier. After using other tools like Charles – Requestly is a nice new breath of air that I highly vouch for. Apart from the tool being amazing – the support from the Requestly team is phenomenal with them always going above and beyond for their clients.
Requestly is an amazing tool to get your development work less hassle. The product itself has evolved so much since day-1 and the company is really serious on helping their customer solves their problems. We had this nice session where they shared Requestly features and we were very impressed on its potential. A truly 5-star worthy.
