MDN HTTP Observatory API
by developer.mozilla.org
Security related services
Added on October 31st, 2026
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What it does
The MDN HTTP Observatory, run by Mozilla, checks how well a website uses security headers and settings such as Content-Security-Policy, HSTS, cookies, redirects and subresource integrity. Send a POST request with a host name and get back a score, a grade and a link to the full report. Responses are JSON. Free, no key needed.
More information: https://developer.mozilla.org/en-US/observatory/docs/api
