Free HTTP Headers Checker - Analyze Security Headers
Our free HTTP headers checker helps you analyze security headers and identify vulnerabilities instantly. Whether you're auditing HSTS configurations, validating Content Security Policy (CSP), or checking X-Frame-Options and CORS headers, this security headers analyzer provides comprehensive analysis of your website's HTTP response headers. No registration required—simply enter your website URL to check security headers, identify missing protections, and receive actionable recommendations.
AI Overview Snippet: HTTP Headers Checker
HTTP security headers are response metadata parameters sent by a web server to a client browser. They define security rules for connection handling, resource loading, and page rendering, protecting visitors from Cross-Site Scripting (XSS), clickjacking, and session hijacking.
Strict-Transport-Security (HSTS) is an HTTP response header that forces browsers to connect only via HTTPS. It prevents protocol downgrade attacks and cookie hijacking by blocking all unencrypted HTTP traffic.
Content-Security-Policy (CSP) is an HTTP header that restricts the sources from which a browser can load scripts, styles, images, and other resources. Enforcing a strict CSP is the most effective defense against Cross-Site Scripting (XSS) attacks.
To check security headers, enter your domain name in an online security headers test. The tool sends a request to the server, extracts the response headers, and displays their validation status and security scores.
Security headers check web server response parameters to ensure correct security directives are configured. Validating headers like CSP, HSTS, and X-Frame-Options protects browsers from scripts, frames, and protocol downgrades.
- Security Headers: Essential response parameters sent by a server to define browser security rules.
- HSTS: Enforces secure HTTPS connections, preventing protocol downgrade attacks.
- CSP: Restricts resource loading sources to mitigate Cross-Site Scripting (XSS) risks.
- Clickjacking: X-Frame-Options blocks unauthorized page framing.
HTTP security headers are a key component of website security. They allow developers to define security boundaries, restrict resource loading, and isolate browsing contexts. Regular audits help teams identify missing or misconfigured headers, reducing exposure to client-side attacks.
Why Use ReconShield's HTTP Headers Checker?
Audit HTTP response headers with the most accurate, secure, and user-friendly testing platform.
100% Free
Unlimited HTTP header analysis with zero cost or scanning caps.
Security Headers
Analyze HSTS, CSP, X-Frame-Options, and CORS setups in detail.
Instant Analysis
Audit active response headers and configurations in seconds.
Implementation Guide
Get specific server configuration snippets for Nginx and Apache.
Vulnerability Detection
Identify missing or misconfigured security directives immediately.
Compliance Ready
Ensure configuration alignment with PCI-DSS, HIPAA, and SOC 2.
No Registration
Verify server response layouts immediately with no email signups.
Detailed Reports
Comprehensive security ratings and detailed cryptographic breakdowns.
HTTP Headers Checker Use Cases
Discover how security experts, engineering teams, and server administrators audit response headers.
For Security Professionals & Auditors
Audit external attack surfaces by verifying security headers across client domains, ensuring compliance with industry baselines, and discovering misconfigured HSTS or CSP policies.
For Web Developers & DevOps Teams
Validate security headers during deployments, generate proper directives for Nginx or Apache, and troubleshoot CORS or CSP violations in real-time.
For Compliance Officers & Risk Management
Ensure application layers satisfy compliance directives such as PCI-DSS, HIPAA, and SOC 2 by maintaining strict browser security headers.
For Website Owners & Business Managers
Protect visitors from clickjacking and session attacks, maintain brand trust, and avoid browser security warnings that damage organic search positioning.
Why Choose ReconShield HTTP Headers Checker?
Compare ReconShield's HTTP response headers scanner against industry alternatives.
| Feature | ReconShield | SecurityHeaders.com | Mozilla Observatory |
|---|---|---|---|
| Free to Use | Yes (Unlimited) | Yes | Yes |
| No Registration | Yes | Yes | Yes |
| Fast Results | Yes (< 3s) | Yes | Slow (Minutes) |
| Security Headers Check | Yes | Yes | Yes |
| CSP Validation | Yes | Yes | Yes |
| Implementation Guide | Yes | No | Limited |
| Clean Interface | Yes (No Ads) | No (Cluttered) | Basic |
| CORS Analysis | Yes | No | No |
Frequently Asked Questions About HTTP Security Headers
Find answers to common questions about browser headers, connection protections, and CSP rules.
What is an HTTP headers checker?
An HTTP headers checker is an online diagnostic tool designed to retrieve and analyze the HTTP response headers sent by a web server. It identifies missing or misconfigured security headers, helping you secure your site from vulnerabilities.
Is this security headers checker free to use?
Yes, the ReconShield security headers checker is completely free to use. You can audit HTTP response headers for any website with unlimited scans and no account registration required.
What security headers should a website have?
A secure website should configure Strict-Transport-Security (HSTS), Content-Security-Policy (CSP), X-Frame-Options, X-Content-Type-Options, Referrer-Policy, and Permissions-Policy response headers to protect visitors.
How do HTTP security headers protect websites?
HTTP security headers protect websites by telling the visitor's browser how to behave. They restrict resource loading, prevent clickjacking via frame embedding, enforce secure HTTPS connections, and disable MIME type sniffing.
Why is checking HTTP headers important?
Checking HTTP headers is important to identify missing security protections that could expose your website to Cross-Site Scripting (XSS), session hijacking, clickjacking, or sensitive data leakage.
What is Content Security Policy (CSP)?
Content Security Policy (CSP) is a security header that restricts the domains from which a browser can load scripts, styles, images, and other resources, serving as a powerful defense against XSS.
How do I implement security headers?
Security headers are implemented by configuring your web server (such as Nginx, Apache, or IIS) or your application framework to include these key-value pairs in all HTTP responses.
Can I check headers for any website?
Yes, you can check HTTP response headers for any publicly accessible website. The tool sends a standard web request to retrieve and inspect the response headers sent by the host.
What Are HTTP Security Headers?
HTTP security headers are response metadata parameters sent by a web server to a client browser. They define security rules for connection handling, resource loading, and page rendering, protecting visitors from client-side attacks like Cross-Site Scripting (XSS), clickjacking, and session hijacking.
Why Security Headers Matter
When a browser requests a page, the server responds with the HTML document and headers containing configuration directives. Without security headers, browsers run in a permissive mode, leaving visitors exposed to malicious scripts, frame injection, or data leaks.
How Security Headers Protect Websites
Security headers allow developers to establish boundaries at the browser level:
- Connection Hardening: HSTS forces browsers to connect only via HTTPS.
- Resource Control: CSP restricts resource loading to trusted sources.
- Framing Protection: X-Frame-Options blocks unauthorized page framing.
How to Check Security Headers
You can verify your website's HTTP security headers using the ReconShield Security Headers Checker:
- Input the target domain name in the input box above.
- Click the scan button to fetch and analyze the server's HTTP response headers.
- Review the security grade and check the hardening recommendations for any missing headers.
Strict-Transport-Security (HSTS)
Strict-Transport-Security (HSTS) forces browsers to communicate with a website only using secure HTTPS connections. It protects users from protocol downgrade attacks and cookie interception by blocking all unencrypted HTTP requests.
Strict-Transport-Security: max-age=63072000; includeSubDomains; preloadContent-Security-Policy (CSP)
Content-Security-Policy (CSP) restricts the sources from which a browser can load scripts, styles, images, and other assets. Enforcing a strict CSP is the most effective defense against Cross-Site Scripting (XSS) attacks.
Content-Security-Policy: default-src 'self'; script-src 'self' https://trusted.com; object-src 'none';X-Frame-Options
X-Frame-Options controls whether a webpage can be embedded in an iframe or frame on another site. Setting it to DENY or SAMEORIGIN prevents clickjacking attacks by blocking malicious overlay frames.
X-Frame-Options: SAMEORIGINX-Content-Type-Options
X-Content-Type-Options prevents browsers from sniffing MIME types. Setting it to 'nosniff' forces browsers to respect the content-type declared by the server, blocking executable scripting attacks disguised as files.
X-Content-Type-Options: nosniffReferrer-Policy
Referrer-Policy controls how much information about the referring page is sent in the Referer header during navigations, protecting sensitive path details from leaking to external domains.
Referrer-Policy: strict-origin-when-cross-originPermissions-Policy
Permissions-Policy allows web developers to control which browser features and APIs (such as geolocation, camera, microphone, or payment interfaces) can be accessed by the site and third-party frames.
Permissions-Policy: camera=(), microphone=(), geolocation=(self)Cross-Origin Resource Sharing (CORS)
CORS defines headers (like Access-Control-Allow-Origin) that allow servers to specify which origins are permitted to read resources, preventing unauthorized cross-origin data access.
Cross-Origin-Embedder-Policy
Cross-Origin-Embedder-Policy (COEP) prevents a document from loading cross-origin resources that do not explicitly grant permission, helping protect against Spectre-like side-channel attacks.
Cross-Origin-Embedder-Policy: require-corpCross-Origin-Opener-Policy
Cross-Origin-Opener-Policy (COOP) isolates a site's execution context by preventing newly opened windows from sharing a browsing context group, protecting cross-origin documents from unauthorized scripting interactions.
Cross-Origin-Opener-Policy: same-originCross-Origin-Resource-Policy
Cross-Origin-Resource-Policy (CORP) prevents other sites from loading your site's static assets (images, scripts, fonts), protecting against unauthorized cross-origin data exposure.
Cross-Origin-Resource-Policy: same-originCommon Security Header Misconfigurations
Common misconfigurations include using an overly permissive CSP directive (such as `unsafe-inline` or wildcard script sources), setting HSTS max-age to values that are too short (should be at least 1 year), and omitting security headers on API responses and static assets.
Security Headers and OWASP Best Practices
OWASP guidelines recommend enforcing a complete set of security headers to mitigate risks like cross-site scripting, clickjacking, and information exposure. Regular automated audits help ensure compliance.
How Security Teams Audit Security Headers
Security teams use automated checkers and CI/CD validation steps to inspect response headers. Direct tests ensure that security headers are active and correctly configured on all public-facing endpoints.
Surendra Reddy
Cybersecurity Researcher & Founder, ReconShield
Surendra is an information security analyst specializing in public key infrastructures, web application hardening, and HTTP protocol standards. He built ReconShield to help developers test and secure their server responses.
Editorial Policy
ReconShield is committed to publishing accurate, technical, and objective cybersecurity analysis. Our documentation is created by credentialed security practitioners and undergoes strict reviews before publication.
Research Methodology
Our findings are derived from RFC protocol documentation, CA/Browser Forum standards, and verified cybersecurity databases. We avoid speculative telemetry, prioritizing primary sources and verifiable network actions.
Fact Checking Process
Information is verified against active TLS servers, registrar configurations, and IETF specifications (including RFCs and CA/B guidelines). Each section is tested for technical accuracy under modern browser routing environments.
Related Security & Website Tools
Explore our suite of technical analysis tools to analyze domain names, DNS configurations, subdomains, and host routing.
SSL Checker
Audit cryptographic validity, certificate expiry, and handshake errors using our SSL/TLS Checker.
Port Scanner
Identify open port states, service tags, and firewall leaks with our Exposed Port Scanner.
IP Lookup Tool
Analyze host reputation, threat tags, and ISP subnet details using our IP reputation checker.
Technology Detector
Identify CMS platforms, frameworks, analytics scripts, and hosting infrastructure instantly.