Security Headers Guide
Learn how browser hardening, content security policy, referrer controls, and related checks fit together.
What you'll find here
Use this guide to move between the key explainers, tools, and checks for security headers and browser-side protections.
Core learn pages
Use these guides to understand what each header does, why it matters, and how to implement it safely.
Free tools
Run live checks for missing headers, referrer leakage, and CSP generation.
Related checks
Use these pages for focused checks around headers, CSP, referrer policy, and related technical setup.