HTTP Observatory
Scan a website for security headers and common web hardening practices.
ABOUT
What is HTTP Observatory?
HTTP Observatory is Mozilla/MDN's free website scanner for HTTP headers and other key web-security configurations. It grades a site and gives actionable recommendations. The old multi-tool Mozilla Observatory, including its separate TLS Observatory, was sunset in October 2024.
BEFORE YOU SIGN UP
What you should know
COMMUNITY
From the forums
Security professionals on r/netsec and r/webdev recommend Mozilla Observatory as a quick and reliable first-pass security audit tool. The scoring system and clear recommendations are appreciated for educating non-security stakeholders about web vulnerabilities. Some users note that the scanner has not been updated as frequently as before and that some checks lag behind evolving security standards like new CSP directives.
— Community sentiment
SEE ALSO · Security
Alternatives to HTTP Observatory
ABOUT US
Honest, independent, no fluff.
No paid placements. Just a clear look at what this does, what it costs, and what to know before you commit.
FAQ
Questions, answered.
Is HTTP Observatory free?＋
Yes. The MDN HTTP Observatory is free and does not require an account. A domain can receive a fresh scan at most once every 60 seconds.
What does HTTP Observatory check?＋
It evaluates HTTP security headers and related web-security configuration. The current MDN version no longer provides the old dedicated TLS and certificate analysis.
Can I use the HTTP Observatory API?＋
Yes. The current v2 scan endpoint is https://observatory-api.mdn.mozilla.net/api/v2/scan and returns metrics such as grade, score and passed or failed tests.