Port Scanner

Scan common ports to check for open services.

What is Port Scanner?

Port Scanner is a security diagnostic tool that checks which network ports are open on a target server or IP address. It helps identify running services, detect potential security vulnerabilities, and verify firewall configurations. This is essential for network administrators testing server security and troubleshooting connectivity issues.

Common Use Cases

  • Security Audits: Check which services are exposed to the internet
  • Firewall Testing: Verify that your firewall is blocking unauthorized ports
  • Service Discovery: Identify what services are running on a server
  • Troubleshooting: Diagnose why certain applications can't connect

How to Use

  1. 1.Enter a hostname or IP address (e.g., example.com)
  2. 2.Click "Scan" to check common ports (21, 22, 25, 53, 80, 443, 3306, 8080)
  3. 3.Review which ports are open or closed

Common Ports Scanned

21 - FTP (File Transfer)
22 - SSH (Secure Shell)
80 - HTTP (Web)
443 - HTTPS (Secure Web)

Common Use Cases

Verify whether expected service ports are open after deployments.
Detect unintended exposed ports on internet-facing hosts.
Validate firewall and security group policy behavior.
Check incident reports for suspicious open services.

Frequently Asked Questions

Is this port scan intrusive?

This scanner checks a defined set of common ports for reachability and is intended for legitimate diagnostics and security hygiene.

Why might a port appear closed?

Ports can appear closed because services are down, firewalls block traffic, or security controls filter probes.

What should I do with unexpected open ports?

Review ownership and necessity, restrict exposure with firewall rules, and disable unused services where possible.

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Last updated: March 10, 2026Built by y4yes Tools Team

Results are generated in real-time. For best accuracy, verify critical issues manually.