A lightweight and secure API Client for faster API Development & Testing

API Collections

Local & Team Workspaces

Import from Postman & Bruno

HTTP Interceptor

A Powerful HTTP Interceptor to Intercept, Record, Debug & Modify HTTP Requests

Replace Rule (Switch Domain)

Modify API Response

Modify Request Body

Modify HTTP Headers

Insert Custom Scripts

Modify Query Param

Cross Device Testing

Block Network Requests

Build frontend faster without waiting for backend.

Modify API responses

Modify API request body

Modify HTTP Status Code

Create Mock Endpoints

Supports GraphQL API Overrides

Frontend Web/Mobile Developers

Requestly improves front-end workflows with local JS testing, mocking, and SessionBook debugging.

For QA engineers

QA engineers love Requestly for its features and ease of use, allowing easy edge case testing.

Support Engineer

Support engineers value Requestly for debugging, demoing, and overriding GTM and Adobe scripts.

Backend Developers

Requestly helps in improving back-end development workflows, by enabling testing.

Requestly vs Postman

Student Programme

Download

Requestly Works on Desktop Only

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Chrome extension

Instant & lightweight. Run the Requestly right inside your browser. Design, test, and mock APIs with collections, environments, and scripts.

More browsers ->

Mac app

Local-first and more powerful. Use the Requestly on your desktop to design, test, and mock APIs across web, mobile, and desktop apps.

Download For Mac

More platforms ->

A lightweight and secure API Client for faster API Development & Testing

API Collections

Local & Team Workspaces

Import from Postman & Bruno

HTTP Interceptor

A Powerful HTTP Interceptor to Intercept, Record, Debug & Modify HTTP Requests

Replace Rule (Switch Domain)

Modify API Response

Modify Request Body

Modify HTTP Headers

Insert Custom Scripts

Modify Query Param

Cross Device Testing

Block Network Requests

Build frontend faster without waiting for backend.

Modify API responses

Modify API request body

Modify HTTP Status Code

Create Mock Endpoints

Supports GraphQL API Overrides

Student Programme

📣 Requestly API Client – Free Forever & Open Source. A powerful alternative to Postman. Try now ->

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Features

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Resources

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Company

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Compliance

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Developers

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Compliance & accreditations

Compare Requestly with

Charles Proxy Wireshark Insomnia

Modheader Fiddler Bruno

Proxyman Mockoon

HTTP Toolkit Postman

Resource Override Hoppscotch

How to Guides

Redirect Your Local Ad Server to Production for 2x Faster Development

Block a header bidding script on websites to isolate testing of other scripts.

Easily Test your Local RTB Scripts on Production Without Deploying

Simplify Demos by Directly Testing Ads on Client Websites

How to Simulate Different Devices Using User-Agent

Test How Your System Handles Geo-Targeting Information

A/B test bundles on production to evaluate their performance.

Case Studies

How Blockthrough uses Requestly to seamlessly test their JS on publisher websites

Breaking Hardware Testing Barriers: Plume’s Journey with Requestly’s API Mocking

From hours to minutes: Stay22’s Journey to Faster Script Deployment with Requestly

Optimizing Ad Delivery with Requestly : Adpushup’s Story