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ToolsWebSecurity Headers
Web

Security Headers

Evaluate HSTS, CSP, X-Frame-Options and related headers, then grade the site's posture.

Enter a value above and run the check to see results here.

How it works

Evaluate HSTS, CSP, X-Frame-Options and related headers, then grade the site's posture.

Related tools

HTTP Header CheckWebsite AvailabilityRobots.txt Checker

Frequently asked questions

Is the Security Headers tool free to use?+

Yes. The Security Headers runs directly in NetInsight with no signup required. Usage is rate limited per IP address to keep the service fast for everyone.

Are my queries logged?+

Diagnostic inputs are processed to produce your result and are not sold or shared. See our Privacy Policy for full detail on retention.

How accurate are the Security Headers results?+

Results are fetched live from authoritative sources each time you run a check, so they reflect the current state rather than a cached snapshot.

More Web tools

Web

HTTP Header Check

Inspect response headers for a URL.

Web

Website Availability

Check whether a site is up and how fast.

Web

Robots.txt Checker

Fetch and summarise a site's robots.txt.