What this tool does
Checks common web security headers and explains what each one does (CSP, HSTS, X-Frame-Options, etc.).
This page focuses on practical, step‑by‑step usage for **Security Header Checker**, with clear examples and common pitfalls.
When you should use it
Use it to harden your website and to interpret scanner findings in plain language.
How to use
- Paste response headers (raw).
- The tool flags missing/weak headers.
- Apply suggested values and retest.
Quick example
Example: Identify missing HSTS and suggest a safe starting max-age for staging vs production.
Notes
CSP is powerful but can break sites—roll out in report-only mode first where possible.
Security Header Checker
Analyze HTTP security headers and identify security misconfigurations
HTTP Security Headers Analysis
This tool analyzes HTTP security headers to identify security vulnerabilities, misconfigurations, and missing security controls on your website.
Critical Security Headers
- Content-Security-Policy (CSP): Prevents XSS attacks by controlling resources
- Strict-Transport-Security (HSTS): Enforces HTTPS connections
- X-Frame-Options: Prevents clickjacking attacks
- X-Content-Type-Options: Prevents MIME type sniffing
- Referrer-Policy: Controls referrer information
- Permissions-Policy: Controls browser features and APIs
- X-XSS-Protection: Legacy XSS protection for older browsers
- Cache-Control: Controls caching behavior
Common Security Issues Detected
- Missing CSP: No protection against XSS attacks
- Weak HSTS: Short max-age or missing preload directive
- Missing X-Frame-Options: Vulnerable to clickjacking
- Insecure CSP Directives: Unsafe-eval or unsafe-inline
- Information Leakage: Server headers revealing technology stack
- Missing Security Headers: Critical headers not implemented
Compliance Standards
- OWASP Security Headers: Minimum security headers required
- PCI DSS: Requires secure configuration
- GDPR: Data protection through security measures
- ISO 27001: Information security management
- NIST Guidelines: Web security best practices
FAQ
Is Security Header Checker encryption?
No. It is primarily an analysis/encoding utility. If you need confidentiality, use a real encryption scheme and manage keys properly.
What should I do if the input fails to decode/parse?
Start by checking for missing padding, wrong alphabet/variant, or extra whitespace. If the data looks multi-layered, try decoding step-by-step (e.g., URL decode → Base64 decode).
Is it safe to paste sensitive data here?
For best security, avoid pasting real secrets (private keys, live tokens, seed phrases). Use test data or work offline, especially for anything that could grant access or move funds.