Analyze TCP port status on remote hosts or server IP addresses using browser WebSocket client connections. Useful for checking firewalls.
Enter a hostname and scan common service ports (21, 22, 80, 443, 3306, 8080).
How Port Scanning Diagnostics Work
A port scanner checks if specific TCP service ports are open and listening on a target host. In proxy networks, open ports (like 80 or 443) facilitate standard web browsing, while other ports run administration services (like SSH on 22 or MySQL on 3306). Checking port states is key to auditing server security configurations.
Scanning Ports via Web Browsers
This tool uses HTML5 WebSocket connection attempts to scan common ports. Because the browser restricts raw socket access, the tool attempts connection handshakes and analyzes response patterns to determine if a port is closed, blocked by a firewall, or open.
Frequently Asked Questions (FAQ)
An open port indicates that a service (such as SSH, HTTP, or Database) is actively listening for incoming connection requests on that port. If exposed publicly without authorization, it can pose a security risk.
A timeout occurs when a firewall silently discards packets sent to that port (filtered). A closed port, on the other hand, immediately sends a reset (RST) packet back to the client.
Yes. Modern web browsers block connection attempts to 'unsafe' ports (like 21 for FTP or 25 for SMTP) for security reasons. Browser-based socket checks work best on HTTP/HTTPS/WebSocket ports.
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