How to Parse & Analyze HTTP Headers

Parse, inspect, and analyze HTTP response headers from any URL. Check security headers, caching rules, and CORS configuration. Free HTTP header parser.

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Step-by-Step Guide

1

Enter a URL or paste headers

Type a URL to fetch its headers, or paste raw HTTP headers directly from your browser DevTools or curl output. The tool accepts both request and response headers in any standard format.

2

View parsed results

Each header is parsed and displayed with its name, value, and a plain-English explanation of what it does. Headers are grouped by category — security, caching, CORS, content, and custom headers.

3

Check security headers

The tool highlights missing security headers like Content-Security-Policy, X-Frame-Options, Strict-Transport-Security, and X-Content-Type-Options. Each missing header includes a recommendation for what to add.

4

Analyze caching and performance

Review Cache-Control, ETag, Expires, and Vary headers to understand how your responses are cached. The tool explains cache behavior in plain language so you can optimize your caching strategy.

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Frequently Asked Questions

What are the most important HTTP security headers?
The essential security headers are: Content-Security-Policy (prevents XSS), Strict-Transport-Security (forces HTTPS), X-Frame-Options (prevents clickjacking), X-Content-Type-Options (prevents MIME sniffing), and Referrer-Policy (controls referrer information). All modern web apps should set these.
What does Cache-Control do?
Cache-Control tells browsers and CDNs how to cache your response. Common directives: max-age=3600 (cache for 1 hour), no-cache (revalidate before using), no-store (never cache), public (CDN can cache), private (browser only). Proper caching dramatically improves page load speed.
What are CORS headers?
CORS (Cross-Origin Resource Sharing) headers control which websites can make requests to your API. Access-Control-Allow-Origin specifies allowed origins, Access-Control-Allow-Methods lists allowed HTTP methods, and Access-Control-Allow-Headers specifies allowed request headers.
Related Reference

HTTP Status Codes Cheat Sheet

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