Port Checker
Check if specific ports are open on any IP address or domain
Check up to 20 ports at once
Enter an IP address and port numbers, then click "Check Ports"
What is a Port Checker?
A port checker is a network diagnostic tool that tests whether specific ports on a server are open and accepting connections. By sending connection requests to designated ports on a target host, it determines if services are running and accessible. Port checking is commonly used for server administration, network security audits, and service availability monitoring.
How to Use
- Enter the target server address in the IP/Domain field
- Enter port numbers to check, separated by commas
- Or use the quick fill buttons for common port presets
- Click "Check Ports" and wait for results
- View each port's status, response time, and any error messages
FAQ
Q: Does "Closed" always mean the port is unavailable?
A: Not necessarily. Browser-based port checking uses HTTP requests, so non-HTTP services (like database ports) may not be accurately detected. Firewall rules can also cause false results.
Q: Why do some ports take so long to check?
A: If a port is filtered by a firewall, the connection will wait for a timeout (about 5 seconds). This is normal and indicates the port may be filtered rather than directly refused.
Q: Which ports can this tool check?
A: In theory, any port in the 1-65535 range. However, browser security restrictions may block access to certain ports (like port 25 or some ports below 1024).
Q: How accurate are the results?
A: Browser port checking is limited by browser security policies and network conditions. Results are for reference only. For precise port scanning, use professional tools like nmap.