Enable debugging mode in applications
Test Different Localizations
Change API Versions
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Effortlessly Customize Query Parameters Without Touching Code
Easily add, remove, or override URL query parameters to streamline testing and development workflows.
Modify Multiple Query Params
Send Additional Information to APIs
Add custom parameters to API calls, such as indicating internal testing Learn more ->
Collaboration & 1-Click Sharing
Promote consistency and accelerate development by sharing Requestly rules within your team. 
More features for your testing needs
These HTTP Rules designed for all your local development and testing needs. Modify Responses Intercept, Modify & Mock API Responses in Real-Time Replace string Replace part of URL like hostname, query values. Redirect URL Redirect any URL to a new destination. Modify Headers Modify HTTP request & response headers. Query params Add or Remove Query Parameters Insert scripts Inject Custom JS & CSS on any website(s). Delay network Simulate delay in response of API calls. Modify request body Modify body of website or application POST requests.