What is the most important HTTP security header?

Content-Security-Policy (CSP) is the most powerful header, restricting which domains and resources the browser is allowed to load and execute.

Web & Network Tools

HTTP Headers Parser & Inspector

Paste raw HTTP response or request header blocks from curl, Postman, or browser network inspectors. Parse them into clear structured key-value tables with instant explanations of each header's purpose and security implications.

Headers are parsed 100% locally in your browser.

HTTP Headers Parser

Browser-based developer converters, network calculators, security analyzers, and SEO generators.

cURL Command Input

JavaScript fetch() Code

fetch("https://api.example.com/v1/data", {
  method: "POST",
  headers: {
    "Authorization": "Bearer my_secret_token",
    "Content-Type": "application/json"
},
  body: JSON.stringify({"name": "Toolxilla", "active": true})
})
  .then(res => res.json())
  .then(data => console.log(data))
  .catch(err => console.error(err));

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How to Use HTTP Headers Parser & Inspector

Paste Raw Headers

Paste multi-line HTTP header text (e.g. 'Content-Type: application/json').

Parse Automatically

Headers are instantly parsed into categorized tables.

Review Insights

Inspect Cache-Control, Cookies, Content-Security-Policy, and CORS configurations.

About HTTP Headers Parser & Inspector

HTTP headers convey metadata governing connection state, caching lifetimes, payload content types, and client-side security sandboxes. Proper header configuration protects web applications against clickjacking, MIME-sniffing, and cross-origin attacks.

Supported Formats

Raw HTTP HeadersJSON

Key Features

Categorizes headers into Security, Caching, Authentication, and Content Negotiation
Highlights missing modern security headers (HSTS, CSP, X-Frame-Options)
Decodes complex multi-parameter headers like Cache-Control and Accept
Parses Set-Cookie directives (Secure, HttpOnly, SameSite, Max-Age)
Zero server logging of sensitive authorization headers

Frequently Asked Questions

Open DevTools (F12) > Network tab, click the top document request, and look at the 'Headers' panel. Click 'view source' next to Response Headers.

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