IP Address Port Checker

FTP - 20 SSH - 22 SMTP - 25 HTTP - 80 IMAP - 993 IMAP - 143 RDP - 3389 SSL - 443 POP3 - 110

What is Open Port Checker?

Port Checker is a simple and free online tool for checking open ports on your computer/device, often useful in testing port forwarding setup on a machine. For instance, if you're facing connection issue with a program (email, IM client etc) then it may be possible that the port required by the application is getting blocked by firewall or ISP. In such cases, this tool might help you in diagnosing the issue. It could also be useful for security reasons, in case you're worried whether a particular port is open or closed.

How to close an open port?

First of all it is necessary to remove the cause - a running program or service that opened the port; it is necessary to close / stop. If the open port reason is not clear - Antivirus scan your computer, delete the extra port forwarding rules on the router and set the advanced firewall (Firewall).

Common Ports

Port-ProtocolDescription
21-FTP File Transfer Protocol - File Transfer Protocol. Port for commands.
22-SSHSecure SHell - "secure shell". Remote Management Protocol operating system.
23-telnetTErminaL NETwork. Protocol implementation text interface over the network.
25-SMTPSimple Mail Transfer Protocol - Simple Mail Transfer Protocol.
43-WHOIS"Who is". Protocol obtaining the registration of ownership of domain names and IP addresses
53-DNSDomain Name System - Domain Name System.
67-DHCPDynamic Host Configuration Protocol - Dynamic Host Configuration Protocol. Dynamic IP
69-TFTPTrivial File Transfer Protocol - a simple file transfer protocol.
80-HTTP / WebHyperText Transfer Protocol - hypertext transfer protocol.
110-POP3Post Office Protocol Version 3 - receive e-mail protocol, version 3
115-SFTPSSH File Transfer Protocol. Secure data transmission protocol.
143-IMAPInternet Message Access Protocol. Application-level protocol for accessing e-mail.
161-SNMPSimple Network Management Protocol - Simple Network Management Protocol. Device Management.
443-HTTPSHyperText Transfer Protocol Secure) - protocol HTTP, which supports encryption.
515-LPDLine Printer Daemon. Remote printing protocol on the printer.
993-IMAP SSLProtocol IMAP, supports SSL encryption.
995-POP3 SSLPOP3 protocol supports SSL encryption.
1080-SOCKSSOCKet Secure. Receiving protocol secure anonymous access.
3128-ProxyCurrently the port often used proxies.
3389-RDPRemote Desktop Protocol - Remote Desktop for Windows.
5900-VNCVirtual Network Computing - a system of remote access to the desktop computer.
5938-TeamViewerTeamViewer - Remote control system for ensuring your computer and data exchange.
8080-HTTP / WebAlternate port for the HTTP protocol. Sometimes used proxies.