Security Headers Checker Online | HTTP Security Headers Grade & Audit

Check which HTTP security headers are present on any website and get an instant A+ to F grade. Verifies Content-Security-Policy, HSTS, X-Frame-Options, X-Content-Type-Options, Referrer-Policy, Permissions-Policy, COOP, and CORP. Designed specifically for developers and professionals, this free online networking runs entirely in your browser to process tasks quickly and securely. Enjoy unlimited usage with no data tracking and no registration required.

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Security Headers Guide

Content-Security-Policy

Tells the browser which sources are trusted for scripts, styles, and media. The most powerful tool against XSS attacks.

Strict-Transport-Security

Forces browsers to use HTTPS for all future requests. Prevents downgrade attacks and cookie hijacking over HTTP.

X-Frame-Options

Prevents your page from being embedded in iframes on other origins. Stops clickjacking attacks cold.

Grading methodology

A+ requires all 8 headers. Each missing header drops your score. F means no security headers at all - high risk.

About Security Headers Checker

Check which HTTP security headers are present on any website and get an instant grade (A+ to F). Verifies Content-Security-Policy, HSTS, X-Frame-Options, X-Content-Type-Options, Referrer-Policy, Permissions-Policy, COOP, and CORP.

Key Features

Checks 8 critical HTTP security headers with pass/fail status
Instant A+ to F grade based on headers present
Shows actual header values so you can inspect configuration
No API key required - works on any public URL
Export full header audit as JSON

Use Cases

Security audits to verify headers before and after deployment
Checking competitor or partner site security posture
Developers configuring Next.js or nginx security headers
Bug bounty research and web application security assessments

Related Keywords

security headers checker

http security headers

check security headers

csp checker online

hsts checker

website security audit

Privacy & Security

Only the URL you enter is sent to the server to make a single HEAD request and read response headers. No page content, cookies, or credentials are transmitted.

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Frequently asked questions

What is Security Headers Checker Online used for?

Is Security Headers Checker Online free to use?

Yes. Security Headers Checker Online is completely free with no usage limits, and there is no paid tier required to use it.

Do I need an account to use Security Headers Checker Online?

No. Security Headers Checker Online works immediately in your browser with no signup, login, or email address required.

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