/.well-known/ checker

About

What is /.well-known/?

A folder reserved by RFC 8615 for site-wide metadata. Instead of every tool inventing its own location, standards register a name in the IANA registry and everyone knows exactly where to look: password managers, mail servers, phone apps, crawlers, AI agents. Older conventions like robots.txt predate it and live at the root of the site. No site needs all of them. Each one only makes sense if you use the thing it describes.

How it works

The checker requests 90 fixed, public paths on the domain you enter, from Cloudflare's network. It never logs in, never follows links, doesn't follow redirects (except example.com ⇄ www.example.com), and reads at most 64 KB of each file. It also requests two random paths to spot servers that answer "200 OK" to everything.

Good to know

• Results are automated and informational. This is not a security audit.
• Some sites block requests from data centers, so an error doesn't always mean a file is missing.
• Domains you check aren't stored, and the site sets no cookies.
• Scans are rate-limited to keep the service free and fair.

For site owners

Requests only happen when someone checks your domain. They use a normal Chrome User-Agent, because many sites stall anything that doesn't look like a browser, and they identify this checker with the header From: https://wellknown.aldiandyainf.com/#about. Questions or problems? Open an issue.