Online Port Scanner
Check open TCP ports on any public server or IP address. Choose a port preset and start scanning.
Port Scanner scans the top-100 popular ports (SSH, HTTP, HTTPS, DB ports, RDP, VNC) in one pass. Reports each as open / closed / filtered. Useful for server security audits — find extraneous open ports before attackers do.
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Why teams trust us
How it works
Enter host or IP
Scan TCP ports in parallel
Get open services list
Why scan ports?
Port scanning shows which TCP ports are open on a server. It helps identify unnecessary services, verify firewall rules, and ensure sensitive ports are closed to external access.
Parallel Scan
Check hundreds of ports in parallel — results in seconds, not minutes.
Service Detector
For each open port show the standard service: HTTP(80), SSH(22), MySQL(3306).
Risk Rating
Critical ports (23, 3389) are flagged as potentially dangerous.
Custom Range
Specify a custom port range for specific audit tasks.
Who uses this
Security
open port audit
DevOps
firewall rule check
Sysadmins
service inventory
Developers
network connection debugging
Common Mistakes
Best Practices
Monitor servers automatically
Ping monitor checks port availability and alerts on changes.
Sign up freeOnline Port Scanner — Check Open Ports for Any Host
This free online port scanner checks whether TCP ports are open or closed on any public server or IP address. It covers the most common ports used by web servers, mail servers, databases, and other network services.
Open ports indicate active services. Unexpectedly open database ports (MySQL, PostgreSQL, Redis, MongoDB) without firewall protection are a serious security risk and should be investigated immediately.
Related guides
Longer-form reading on this topic from the knowledge base.
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