> ## Documentation Index
> Fetch the complete documentation index at: https://docs.requestly.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Browser Extension 

> Learn how to use Browser Extention to intercept HTTP Request and Responses

**Requestly Interceptor’s browser extension** is the simplest way to intercept and modify HTTP requests and responses directly **within your browser**. It’s lightweight, easy to install, and perfect for debugging frontend issues or simulating API responses, without needing to run a local proxy or configure complex setups.

Whether you're a frontend developer testing new **API integrations** or a QA engineer simulating error scenarios, the browser extension gives you powerful tools right in your development environment.

### Key benefits

* **No proxy setup required** – Works entirely within the browser.
* **Quick debugging** – Instantly view, rewrite, or mock API requests.
* **Cross-browser support** – Available for Chrome, Firefox, Edge, and more.
* **Secure and isolated** – Only affects traffic in the browser you install it on.

### When to use the browser extension

Use the browser extension if:

* You only need to intercept traffic from websites or web apps.
* You’re testing frontend behavior and want a quick setup.
* You want to create rules to mock APIs, rewrite URLs, inject scripts, or modify headers.

### How to intercept traffic using the extension

Once the browser extension is installed, you can start intercepting traffic with just a few clicks.

[Follow the Browser Interception guide to get started →](/http-interception/interceptor/browser-extension/browser-interception)

This guide walks you through launching a connected browser, viewing traffic in the network table, and verifying the proxy setup.

[Requestly Interceptor’s Browser Extension is a lightweight interceptor](/http-interception/interceptor/browser-interception) that runs directly in your browser. It allows you to intercept, modify, and control both incoming responses and outgoing requests, making it a powerful tool for developers and testers.

## **Browser extension features**

With the browser extension, you can:

* [**Modify requests**](/http-interception/http-rules/rule-types/modify-request-body) – Change headers, query parameters, or request methods before they’re sent.
* [**Mock responses**](/http-interception/api-mocking/api-mocking) – Return custom JSON or status codes instead of hitting the real server.
* [**Redirect traffic – Route**](/http-interception/interceptor/desktop-app-interception) API calls to staging or mock URLs for flexible testing.
* [Inject](/http-interception/interceptor/desktop-app-interception)[**scripts/styles**](/http-interception/http-rules/rule-types/insert-scripts) – Add custom JavaScript or CSS into pages on the fly.

Learn more about how to work with browser interceptor [here.](/http-interception/interceptor/desktop-app-interception)

## Supported Browsers & Profiles

Requestly Interceptor supports all modern browsers, and you can use it with many browsers like Google Chrome, Firefox, and Safari. Here’s a breakdown of the browser support:

* **Chromium-Based Browsers**

  Requestly Interceptor is available on all Chrome-based browsers through the Chrome Web Store. This includes Google Chrome, Microsoft Edge, Brave, Opera, and others.
* **Firefox**

  We officially support Firefox, ensuring a seamless experience for Firefox browser.
* **Safari (limited support)**

  The Requestly Interceptor extension is available for Safari with a smaller feature set today. Full support for HTTP rules is coming soon.