Open Source
Automate & change webpage's behaviour with JS & CSS
Customise any Webpage using Requestly’s Insert script Rule. Add Custom JavaScript (JS) or Styles (CSS) Remove/hide unwanted sections, add action buttons, add your own libraries to support your script, etc.

Inject Custom Javascript
Inject custom JavaScript code into a webpage. This feature enables you to modify the behavior or appearance of a website by running your own scripts
Inject Custom CSS
Inject custom CSS styles into a webpage and override existing styles or add new styles to elements on a website
Multiple Scripts Support
Supports the execution of multiple scripts simultaneously on a webpage. This feature allows you to combine and apply multiple JavaScript or CSS injections to a website.
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Application and use cases
Here’s how you can use Requestly’s Insert Custom Scripts feature in your daily workflow

Inject custom JavaScript
You can use Requestly to inject custom JS on your specified URL. The possibilities for testing and modifications are endless with Requestly

Inject custom CSS
You can let Requestly inject custom CSS on your specified URL, letting you test and verify your styles

Load & Demo SaaS Apps
You can directly insert the installation code that you get for integration from the 3rd party app and try it on your website
Intercept & Modify HTTP Requests
Boost Your Web Development: Advanced Tools for Seamless Debugging.
Redirect URL (Map Remote)
Redirect a request URL to another URL. e.g. Load local scripts in the production sites for faster debugging.
Override API Response
Test edge cases in your app by simulating API responses. Override XHR, fetch and AJAX responses.
Inject Custom Scripts
Add Custom JavaScript (JS) to Hide unwanted sections, add action buttons, inject your own libraries, etc.
Modify HTTP Headers
Add, Delete, Override Request & Response Headers. Can be used to remove X-Frame-Options, Content-Security-Policy, CORS Issues, etc.
Modify Query Params
Insert, Modify or Delete query parameters for URLs (or matching pattern). Burst cache for a request by assigning it a newer version.
Delay HTTP Requests
Simulate lag / delay to the response from specific URLs in a single click by using Requestly’s Delay Request Rule. No need to modify actual server.
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