HSTS Header Checker 🔐
Test your website's HTTP Strict Transport Security headers instantly. Verify HSTS implementation, check preload eligibility, and ensure your website security is properly configured.
Enter a domain name without http/https (e.g., example.com)
How HSTS Header Checker Works
Enter Domain
Type the domain you want to check without http/https protocol
Instant Analysis
Our tool fetches and analyzes HTTP headers in real-time
Get Results
Receive detailed report on HSTS configuration and recommendations
Key Features of Our HSTS Checker
Instant Header Scan
Quickly test any website for HSTS header presence and configuration
Shows All Headers
View all HTTP response headers including security headers
Preload Eligibility Check
Verify if your domain meets HSTS preload list requirements
Security Best Practices
Get recommendations to improve your website security
Frequently Asked Questions
HSTS (HTTP Strict Transport Security) is a security policy mechanism that helps protect websites against protocol downgrade attacks and cookie hijacking. It allows web servers to declare that web browsers should only interact with it using secure HTTPS connections.
To enable HSTS, add the following header to your server configuration:Strict-Transport-Security: max-age=31536000; includeSubDomains; preload
Note that the "preload" directive is optional and requires submission to the HSTS preload list.
HSTS protects against several types of attacks including SSL stripping, man-in-the-middle attacks, and cookie hijacking. It ensures that browsers always connect to your website using HTTPS, even if the user types "http://" explicitly.
The HSTS preload list is a list of domains that are hardcoded into web browsers as HTTPS-only. Once your domain is on this list, browsers will automatically use HTTPS even before the first visit, providing maximum security protection.
Once the HSTS header is implemented, it takes effect immediately for returning visitors. For first-time visitors, the protection begins after the initial HTTPS connection. For maximum protection, consider submitting your site to the HSTS preload list.