Getting Started
Installation
Rex is a Chrome extension available on the Chrome Web Store:
- Visit the Rex listing on the Chrome Web Store
- Click Add to Chrome
- Confirm the installation when prompted
After installation, click the Rex icon in your toolbar to open the app.
Your First Request
- Type a URL in the URL bar (e.g.,
https://jsonplaceholder.typicode.com/posts/1) - Select a method from the dropdown (defaults to GET)
- Press Cmd+Enter (macOS) or Ctrl+Enter (Windows/Linux) to send
- The response appears in the panel below with syntax highlighting, status code, timing, and size
That’s it — no setup, no accounts, no configuration.
The Interface
Rex is organized into a few key areas:
Sidebar
The left sidebar contains your Collections (saved requests), History (automatic log of every request), Environments (variable sets), and Chains (request sequences). Toggle it with Cmd+B.
URL Bar
The top bar where you enter the URL and select the HTTP method. Paste a cURL command here and Rex auto-parses it into a full request configuration.
Request Tabs
Below the URL bar, tabbed panels let you configure:
- Params — Query string parameters
- Headers — Request headers with auto-complete
- Body — JSON, form-data, URL-encoded, raw text, or GraphQL
- Auth — Authentication configuration (7 methods)
- Scripts — Pre-request and test scripts
- Cookies — View and manage cookies
Response Panel
Shows the response with content-aware rendering: syntax-highlighted JSON, inline HTML preview, image display, PDF viewer, XML formatting, or hex dump for binary data. Tabs for Body, Headers, and Cookies.
Working with Tabs
Rex supports multiple tabs so you can work on several requests at once:
Each tab maintains independent request and response state. Tab state persists across sessions.
Saving Requests
Press Cmd+S to save the current request to a collection. Choose an existing collection or create a new one. Saved requests include the full configuration: URL, method, headers, body, auth, and scripts.