Rex
Fast, keyboard-driven REST API client that lives in your browser
A full-featured API client built as a Chrome extension. Craft requests with a visual editor, organize them into collections, chain dependent calls, write test scripts, and generate code — all without leaving your browser. Supports REST, GraphQL, WebSocket, and Server-Sent Events.
Features
Request Builder
Visual editor for HTTP requests with params, headers, body (JSON, form-data, GraphQL, raw), cURL parsing, and real-time variable interpolation.
Collections & Tabs
Save requests into named collections, work on multiple requests in parallel tabs, and drag-and-drop to reorder. All state persists across sessions.
Environments & Variables
Define variable sets for dev, staging, and production. Reference them anywhere with {{variable}} syntax. Switch environments with one click.
7 Auth Methods
Bearer, Basic, API Key, OAuth 2.0 (authorization code, client credentials, PKCE), AWS Signature V4, Digest, and mTLS — all built in.
Scripts & Testing
Pre-request and test scripts with a JavaScript API. Set variables, modify headers, assert on responses, and chain requests with pass/fail reporting.
WebSocket & SSE
Connect to WebSocket endpoints with real-time messaging, or stream Server-Sent Events with auto-scroll and payload inspection.
More Highlights
Code Generation
Generate working snippets in JavaScript (Fetch, Axios, Node.js http), Python (requests, httpx), and cURL from any request
Import & Export
Import from Postman, OpenAPI/Swagger, HAR, and cURL. Export to Postman, HAR, cURL, JSON, or shareable Rex links
Response Viewer
Syntax-highlighted JSON, inline HTML preview, image display, PDF viewer, XML formatting, and hex dump for binary data
Request Chaining
Build sequences of dependent requests that execute in order. Extract response values into variables for the next step
DevTools Panel
Capture live network requests from any page via the DevTools panel and send them to Rex or bulk import as a collection
History & Diff
Every request is logged automatically. Search, filter, and compare any two history entries with a side-by-side diff viewer
GraphQL
Dedicated GraphQL mode with schema introspection, autocomplete for types, fields, queries, and mutations
Cookie Editor
View, inspect, and delete cookies for any domain directly from the browser's cookie jar
Keyboard-First
Cmd+Enter to send, Cmd+S to save, Cmd+B to toggle sidebar — fast workflow without touching the mouse
Installation
Install Rex from the Chrome Web Store, then click the extension icon or open it from a new tab. Start building requests immediately — no account or setup required.