Security headers summary for t-online.de
This page validates the HTTP security headers returned by t-online.de, scoring its protection against common web attacks.
Below you can review which headers t-online.de sends, which are missing, and recommendations to harden the configuration.
What are HTTP security headers?
HTTP security headers are response headers that instruct the browser to apply protective policies, mitigating attacks such as XSS, clickjacking and content sniffing.
Key headers include Content-Security-Policy (CSP), Strict-Transport-Security (HSTS), X-Frame-Options, X-Content-Type-Options and Referrer-Policy.
How to interpret the headers of t-online.de
A higher score means t-online.de sends more of the recommended security headers with secure values. Missing headers are highlighted so you know what to add.
Focus first on CSP and HSTS for t-online.de, as they provide the strongest protection against scripting and downgrade attacks.
Use cases
- Audit the security headers of t-online.de before or after a deploy.
- Identify missing headers that increase attack risk on t-online.de.
- Verify that t-online.de enforces HTTPS with HSTS.
- Support hardening reports and security reviews for t-online.de.
Frequently asked questions
Which security headers does t-online.de use?
This page lists the HTTP security headers present on t-online.de, such as CSP, HSTS, X-Frame-Options and X-Content-Type-Options, along with their values.
Does t-online.de have a Content-Security-Policy?
The results show whether t-online.de sends a Content-Security-Policy header and whether its value is considered secure.
Does t-online.de enforce HTTPS with HSTS?
The Strict-Transport-Security section indicates whether t-online.de forces HTTPS and for how long, including includeSubDomains and preload flags.
Why does t-online.de have a low security score?
A low score means t-online.de is missing important headers or sends insecure values. The missing-headers and recommendations sections explain how to improve it.
Is the security headers check for t-online.de free?
Yes. The XploreNetHub Security Headers Validator is completely free, requires no sign-up and runs directly in your browser.
Related guides
- Security Headers Checklist — HSTS, CSP and HTTP headers before go-live.
- DNS and SSL Checklist — Steps and verification table before pointing a domain.