Check that the service behind a port is still accepting connections, not just that the server answers a ping. Watch your mail, database, SSH, and FTP ports from 15+ global locations.
Make sure databases and other services running on different ports on your server are always available. We support any port, including HTTPS, FTP, SSH, ...
Set up a POP3, IMAP and SMTP port monitoring and know about any issues with your essential email services.
With port monitor watching your DNS port you always know whether essential DNS connection is okay.
Get instant alerts via email, SMS, voice call or through one of many integrations (such as Slack, Zapier, Splunk, etc.)
Be the first who knows that your website is down. Reliable monitoring warns you before any significant troubles and saves you money.
Set threshold and recurrence parameters so that you don't miss any serious outage.
Set up maintenance windows to pause the monitoring during the maintenance.
Create monitors with specific monitoring regions you can choose and catch issues that only appear in specific locations.
No internet? We can call or text you when something goes wrong.
Multi-location checks, response time tracking, SSL and domain expiry alerts. The details that turn raw uptime data into something you can actually act on.
From Websites and APIs to servers and cron jobs, UptimeRobot watches every layer. Nine monitor types, one dashboard.
Be transparent. Share your uptime with the public and inform your customers about any planned (or unplanned) outages.
You can invite all your team members to access your monitors, keep them notified and manage incidents. Choose from three levels of user access: read, write and notify-only.
Get notified the instant something breaks: by email, SMS, Phone call, Slack, or webhook. Watch your whole stack from one place and pick the channels that reach your team fastest, so critical issues never sit unseen.
Improved network security by keeping an eye on open ports
Tracking status and performance of network devices
Enhanced troubleshooting and reduced incident response time
We strive for minimal downtime, but if something goes wrong UptimeRobot makes sure that we know about it quickly.
We switched to using UptimeRobot years ago as they offered the same services we were getting from a different provider but at a fraction of the cost.
Port monitoring checks whether a specific TCP port on your server is open and accepting connections. A server can answer a ping while the service running on it has stopped responding. Port monitoring catches that gap by testing the port itself, so you know the actual service, your mail server, database, or SSH, is reachable and not just the machine.
What metrics are monitored?
A port monitor tracks:
Checks run from multiple global locations, so a single regional network blip doesn't trigger a false alert. On paid plans you can also set slow-response alerts and recurring notifications.
Why use port monitoring?
Some of your most important services don't run on the web port. Email (SMTP, IMAP, POP3), databases (MySQL, PostgreSQL), SSH, FTP, and DNS each listen on their own port, and an HTTP or ping check won't tell you when one of them goes down. Port monitoring watches those services directly. If your SMTP port stops accepting connections, you find out before customers report that email isn't arriving.
UptimeRobot supports monitoring any TCP port, including standard ports for web servers, email services, databases, DNS, SSH, FTP, and custom applications.
Common examples include:
If your service uses a non-standard port, you can enter any custom TCP port manually when creating the monitor.
Port monitoring checks whether a specific service is accepting TCP connections on a given port. Ping monitoring checks whether the server itself is reachable over the network using ICMP.
A server can still respond to ping requests while services like SSH, databases, or mail servers are down. Port monitoring goes one step further by verifying that the actual service behind the port is running and accessible.
For broader visibility, many teams use both ping and port monitoring together.
Monitor any service your users, applications, or infrastructure depend on. Common examples include:
Port monitoring detects when a service stops accepting connections, even if the server itself is still online.
Yes, port monitoring is a reliable way to monitor mail server availability. UptimeRobot supports SMTP (25, 465, 587), IMAP (143, 993), and POP3 (110, 995) ports.
If any of those services stops accepting connections, you receive an alert immediately. Email issues often go unnoticed longer than website outages, so monitoring mail ports directly helps catch problems earlier.
To create a port monitor in UptimeRobot, enter the hostname or IP address of your server, specify the TCP port you want to check, and choose how often the monitor should run.
You can also configure alert integrations like email, Slack, Microsoft Teams, SMS, or PagerDuty notifications. When the monitor is saved, UptimeRobot starts checking the port automatically and alerts you if the service stops accepting connections.
Yes, UptimeRobot includes free port monitoring with automatic uptime checks, response time tracking, and email alerts.
Paid plans add faster monitoring intervals, more monitors, and additional notification integrations like Slack, Microsoft Teams, SMS, voice calls, and PagerDuty alerts.
Yes, each port monitor checks one specific server and TCP port combination, so monitoring multiple ports on the same server requires separate monitors.
For instance, you can monitor HTTPS on port 443, SSH on port 22, and MySQL on port 3306 at the same time. Each monitor runs independently and sends alerts separately, making it easier to identify which service is affected.
Looking for the best cost-effective port monitoring that meets all your needs? Read our detailed guide focusing on key features and pricing.
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