HSTS Header Checker

Free HSTS Header Tester – Secure Your Website with HTTPS Strict Transport Policy

The HSTS Tester tool helps website owners, developers, and cybersecurity professionals verify if a website enforces HTTPS through the HSTS response header. This tool checks for the presence of the `Strict-Transport-Security` header and its directives such as `max-age`, `includeSubDomains`, and `preload`.

Why HSTS Matters 🔐

• ✅ Prevents protocol downgrade attacks
• ✅ Increases trust and HTTPS enforcement
• ✅ Required for HSTS Preload List in browsers
• ✅ Essential for modern web security practices

How to Use:

1. Enter your domain name (without http/https)
2. Click "Check HSTS"
3. Review the HSTS header details (if present)

To preload your domain in browsers like Chrome or Firefox, your header must contain:
Strict-Transport-Security: max-age=31536000; includeSubDomains; preload

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