HTTP Security Headers & CSP Policy Evaluator
Audit and generate production security headers (HSTS, CSP, X-Frame-Options, Permissions-Policy, COOP, CORP).
Execution runs 100% locally inside the browser sandbox using HTML5 Canvas, Web Cryptography Subtle API, and Web Workers. No data is ever transmitted across the network.
Zero network latency. Operates completely offline with zero dependencies on third-party backend servers or cloud services.
Built according to official RFC specifications, cryptographic test vectors, and enterprise-grade data transformation standards.
How to Use HTTP Security Headers & CSP Policy Evaluator
Toggle HSTS, CSP, X-Frame-Options, Referrer-Policy, and COOP isolation flags.
Verify your server security rating (Grade A+, A, B) based on enabled directives.
Copy ready-to-paste configurations for Next.js, Nginx, Apache, Caddy, or Cloudflare.
Frequently Asked Questions
What is HSTS preload?
HSTS preload registers your domain on browser-enforced HTTPS lists maintained by Google and Mozilla, guaranteeing connections never start with unencrypted HTTP.
What is the difference between COOP and CORP?
COOP (Cross-Origin Opener Policy) prevents malicious cross-origin popups from accessing your window object. CORP (Cross-Origin Resource Policy) prevents unauthorized sites from embedding your protected media and API responses.
How do I add these headers to Next.js App Router?
Copy the exported 'headers()' async function from the Code tab into your project's next.config.ts or next.config.mjs file.
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