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Open Port Checker
Check whether a common service port (web, mail, SSH, database) on a public server accepts connections from the internet.
Good to know
About the Open Port Checker
Want to know before it breaks?
KeepUpTime checks this for you around the clock and alerts you by email, WhatsApp or Slack. Plans from $15 per month with a 3-day free trial.
Start free trialWhy is my port closed?
The service may be stopped, a firewall may block it, or your host may not allow that port. Closed is good for databases that should not be public.
Which ports can I check?
Common service ports such as 22 (SSH), 25/465/587 (mail), 80/443 (web) and database ports. Arbitrary port scanning is not allowed.
Can I get alerts when a port goes down?
Yes. Add a Server port (TCP) monitor in KeepUpTime and you will be alerted when it stops accepting connections.