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    HTTP Security Headers Checker

    HTTP security headers tell the browser how to safely render your site — blocking clickjacking, XSS, mixed content, and MIME sniffing attacks. This tool fetches your homepage, inspects the response headers, and gives you a 0–100 score plus copy-paste fixes for whatever's missing.

    Frequently asked questions

    What's the most important security header?

    Strict-Transport-Security (HSTS) — it forces every connection to use HTTPS and prevents protocol-downgrade attacks. Set max-age=31536000; includeSubDomains; preload.

    Is X-Frame-Options still needed if I have CSP?

    If your CSP includes a frame-ancestors directive, X-Frame-Options is redundant for modern browsers — but X-FO still helps older clients. Either is fine.

    Why don't I have Content-Security-Policy?

    CSP is the highest-impact header but the trickiest to roll out without breaking your site. Start in Content-Security-Policy-Report-Only mode and tighten over time.

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