API Tester Pro - REST Client, HTTP Request Builder, Debug & Collections

API Tester Pro is a fast, full-featured REST client and API testing tool that runs entirely inside your browser. Send HTTP requests, inspect responses, debug APIs, and manage saved collections — without installing a heavy desktop app.

KEY FEATURES: • Send GET, POST, PUT, PATCH, DELETE, HEAD, and OPTIONS requests • View formatted response body, headers, status codes, and timing • Syntax-highlighted JSON, XML, and HTML response viewer • Authentication support — Basic Auth, Bearer Token, API Key, OAuth headers • Request body support — JSON, form data, raw text, and binary • Save and organize requests into collections for reuse • Request history — quickly re-send previous API calls • Import and export collections for team sharing • Environment variables for switching between dev, staging, and production

A lightweight REST client alternative that's fast and private. No signup. No cloud dependency. Install and start testing.