Free tools / Security headers checker
Which security headers is your site missing?
Six response headers that a standard asks for and a server can add in a line each. The check reads the response as a crawler would and reports the ones that are missing, with the value to add.
Questions
Do security headers affect SEO?
HTTPS does directly; the rest affect trust and the browser's protection of your users. They sit in the audit's security category, which is part of the overall score.
Which one matters most?
Strict-Transport-Security on any site that serves HTTPS, and a Content-Security-Policy on any site that runs third-party scripts. The rest are one line each.
Why are DMARC and SPF here?
They are DNS records for the domain's mail, not response headers, but a site without them has its domain spoofable in email, and the audit reports them in the same category.
The other free checks
- AI crawler access checker
- robots.txt AI crawler checker
- llms.txt checker
- Sitemap checker
- Structured data checker
- Full SEO and AI-search audit
- AI visibility checker
All of them run locally too: npx @rankcli/cli audit --url yoursite.com.