API & HTTP Tools
Test REST APIs, debug WebSocket connections, and edit OpenAPI specs. Free online API tools for developers — all 100% browser-based. Send HTTP requests, inspect responses, test WebSocket real-time communication, and design API specifications. No backend required, everything runs in your browser.
API Tools Hub
Explore REST API client, WebSocket tester, OpenAPI editor, JWT tools, and more.
REST API Client
Send HTTP requests and view responses.
WebSocket Client
Test WebSocket connections in real-time.
OpenAPI Editor
Edit and preview OpenAPI specifications.
OpenAPI Diff
Compare two OpenAPI specs side by side.
API Mock Response Generator
Generate realistic mock JSON responses for REST API endpoints using Faker.js.
URL Encoder
URL-encode query parameters for API requests.
JWT Encoder
Create JWT tokens for API authentication.
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