Security Headers Checker

// Check and analyze HTTP security headers

Content-Security-Policy
critical

Controls which resources the browser can load. Mitigates XSS and data injection attacks.

Recommended: default-src 'self'; script-src 'self'; style-src 'self' 'unsafe-inline'
Strict-Transport-Security
critical

Forces HTTPS connections. Prevents protocol downgrade attacks and cookie hijacking.

Recommended: max-age=63072000; includeSubDomains; preload
X-Content-Type-Options
high

Prevents MIME-type sniffing. Reduces drive-by download attacks.

Recommended: nosniff
X-Frame-Options
high

Controls whether the page can be embedded in iframes. Prevents clickjacking.

Recommended: DENY
X-XSS-Protection
low

Legacy XSS filter for older browsers. Modern browsers rely on CSP instead.

Recommended: 0
Referrer-Policy
medium

Controls how much referrer information is shared with other sites.

Recommended: strict-origin-when-cross-origin
Permissions-Policy
medium

Controls browser features like camera, microphone, geolocation.

Recommended: camera=(), microphone=(), geolocation=()
Cross-Origin-Opener-Policy
medium

Isolates browsing context. Prevents Spectre-like side-channel attacks.

Recommended: same-origin
Cross-Origin-Resource-Policy
medium

Controls which origins can load your resources.

Recommended: same-origin
Cross-Origin-Embedder-Policy
low

Controls embedding of cross-origin resources. Required for SharedArrayBuffer.

Recommended: require-corp

#About Security Headers Checker

Free online security headers checker. Analyze HTTP response headers for security best practices including CSP, HSTS, X-Frame-Options, and more. This tool runs entirely in your browser — your data is never sent to a server. Just paste your input, get instant results, and copy with one click. No sign-up or installation required.

#FAQ

Which security headers are most important?
Content-Security-Policy (CSP) and Strict-Transport-Security (HSTS) are the most critical. CSP prevents XSS and injection attacks, while HSTS ensures all connections use HTTPS. X-Content-Type-Options and X-Frame-Options are also high priority for preventing MIME sniffing and clickjacking.
How do I get my response headers to paste here?
Open your browser DevTools (F12), go to the Network tab, reload your page, click on the main document request, and look at the Response Headers section. You can copy the headers from there. Alternatively, use curl -I https://yoursite.com in your terminal.
</> Embed this tool

Copy this code to embed the tool on your website. Adjust the height to fit your layout.

<iframe src="https://www.browserutils.dev/embed/security-headers-checker" width="100%" height="500" frameborder="0" title="Security Headers Checker"></iframe>

#Related