# HeaderSec

> HeaderSec is a free HTTP security header scanner and educational resource. It checks public URLs for defensive browser headers and explains how to improve them.

## Core pages

- [HTTP Security Header Scanner](https://headersec.com/)
- [Security Headers Guide](https://headersec.com/learn/security-headers)
- [HeaderSec API Documentation](https://headersec.com/docs/api)

## What HeaderSec checks

HeaderSec reports on Strict-Transport-Security, Content-Security-Policy, clickjacking defenses, X-Content-Type-Options, Referrer-Policy, Permissions-Policy, cookie attributes, cross-origin isolation, and avoidable server information leakage.

## Important scope note

A HeaderSec result is a focused configuration check, not a complete vulnerability assessment or proof that a website is secure.