Port Checker
Check whether a public host accepts a TCP connection on a port. See connection results from our server and understand timeout limitations.
TCP connectivity
A clear result, then the details.
Enter a domain or public address above. Your result will appear here with a readable explanation.
Nothing is scanned until you run the check.Technical details · colour-coded JSON
About
Check whether a public host accepts a TCP connection on a port. See connection results from our server and understand timeout limitations.
Reachable is not the same as healthy
A successful TCP handshake shows that a connection was accepted. It does not verify a web page, mail delivery or application login.
Understand an unsuccessful check
Refused means a rejection was observed; a closed listener or firewall can reject. Timeout means no connection completed within three seconds, not proof of filtering or a closed port. Try example.com on TCP 443 to see a typical HTTPS listener. This is not a UDP test and does not test from your home network.
Try this
Enter https://example.com and port 443. A connection establishes reachability from our server; if your own browser still fails, check its DNS, proxy and local network separately.
Network checks originate from the WhatsMyIP server. Only public destinations are accepted. Timeouts may reflect filtering or network conditions rather than a faulty website.
Use the result as one part of your troubleshooting. Network information can change over time.
A useful next step
- Check DNS records — Confirm the hostname points to the expected public address.
- Public vs private IP addresses — Work out why a local router or device address cannot be tested from our server.
- Check TLS on HTTPS — A reachable port does not verify its certificate.