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HTTP Header Checker

Inspect HTTP response headers and status codes from any URL. Analyze security headers, caching directives, and server information.

Status Code Tester

Look up any status code number across all 7 protocols. See what 200, 404, or 503 means in HTTP, gRPC, SIP, and more.

Mock Response Generator

Generate realistic mock HTTP responses with custom status codes and headers. Copy ready-to-use curl commands and code snippets.

API Response Mock

Get ready-to-use code snippets to mock any status code in Django, Flask, FastAPI, Express.js, Spring Boot, Go, Rails, and ASP.NET.

Redirect Tracer

Trace the full redirect chain for any URL. See every hop — 301, 302, 303, 307, 308 — with status codes, locations, and timing.

JWT Decoder

Decode and inspect JSON Web Tokens. View header, payload, and signature details — entirely in your browser, nothing sent to any server.

CORS Checker

Check CORS (Cross-Origin Resource Sharing) headers for any URL. Verify allowed origins, methods, headers, and credentials support.