Reachability Checker

This runs tests in the browser, so results reflect the connectivity of the device running the page. Some details such as HTTP status may be unavailable unless the target supports CORS.

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Environment

Test profile

Timeout per target

Milliseconds

Show advanced details Attempt CORS status fetch when possible Stop on first failure

Results

Select a profile and run.

How to read the output

Reachable means the browser could open a connection and receive some response. With no CORS, the browser may not reveal the HTTP status.
Blocked or unreachable usually means DNS failure, firewall, proxy block, TLS failure, or a timeout.
Opaque response means the request succeeded but the browser withheld response details due to cross origin rules.