Port Scanner is a free tool that helps you find open ports on your device with ease. It automatically finds your IP address and checks your device for open and unprotected ports that hackers, viruses, and Trojans could use to break into your system.
What is Online Port Scanner
Open Ports Scanner, powered by nmap, checks your device to find system ports that might be open and at risk. Here's what it can do for you:
- The scanner quickly finds active system ports that are ready to send or receive data.
- By detecting open port activity, you can see what apps and services are running on your system.
- Port scanning is a simple way to help keep your device safe from hackers.
What is Network Ports
A network port serves as a communication endpoint that a system assigns to an application or service, allowing it to exchange data with other devices or hosts, and even with other programs on the same device. Each network port is identified by a number ranging from 0 to 65535. This port number, along with the IP address, is included in the packet header to direct the network traffic accurately. An application uses a port to either send out a request to or receive data from a corresponding open port on another device, facilitating the connection for the designated service.
Why Port Scanning Is Important
Websites can scan locally open ports and detect which ports are opened on a computer to learn which programs the user is running. We learned that Facebook, eBay and Amazon all use such technical means.
In computer science, a port is a communication endpoint. When an application runs on a computer, it opens a port, which corresponds to the address through which the application interacts with other applications.
For example:
- TeamViewer will open ports: 80, 443 and 5938 (TCP)
- RDP (Remote Desktop Protocol) will open port: 3389 (TCP/UDP)
Through port scanning, the website can help determine whether the user has performed operations not allowed by the platform through remote control of the VPS and other means, thereby banning the account.
Common Ports
Our port scanner is designed to detect open ports that are commonly targeted by hackers. These ports are known points of entry that can be exploited for unauthorized access, data breaches, or to take control of devices. The Nmap database, a popular network security tool, lists the most frequently scanned ports by attackers. It's crucial to monitor and secure these ports to protect against potential intrusions.
Here's a table with explanations of each port and its common use:
- 20,21-FTPUsed for file transfers between systems
- 22-SSHSecure shell access to remotely manage systems
- 23-TelnetUnsecured text-based remote login service
- 25-SMTPStandard protocol for email transmission
- 53-DNSDomain Name System service for resolving names to IP addresses
- 80-HTTPStandard protocol for web traffic
- 110-POP3Protocol used by email clients to retrieve messages from server
- 111-RpcbindService that maps RPC services to network ports
- 135-MSRPCMicrosoft Remote Procedure Call for networked client/server communication
- 138-NetBIOS-DGM, trojanUsed for network file sharing and known for vulnerabilities
- 139-NetBIOS-SSN, trojanAnother port for network file sharing and known for vulnerabilities
- 443-SSL / HTTPSSecured web traffic via SSL/TLS encryption
- 445-Microsoft-DSUsed for Windows file and printer sharing and other services
- 502-Modbus ProtocolCommunication protocol mainly used for industrial automation
- 587-SMTPAlternative port for email transmission, often secured
- 993-IMAPSSecure version of IMAP, using SSL/TLS encryption
- 995-POP3SSecure version of POP3, using SSL/TLS encryption
- 1080-Socks-proxyPort for SOCKS proxy servers
- 1723-PPTPPoint-to-Point Tunneling Protocol for VPNs
- 2525-SMTPAnother alternative port for SMTP, used when others are blocked
- 3124-Beacon-portKnown for being used by certain malware
- 3127-ProxyCommonly used for proxy servers and anonymizing services
- 3128-ProxyAnother port often associated with proxy services
- 3306-MySQLDefault port for MySQL database server
- 3389-MS WBT ServerUsed for Microsoft Remote Desktop (RDP)
- 5000-TrojanKnown to be used by some trojans and malicious software
- 5900-VNCUsed for Virtual Network Computing (remote desktop software)
- 8080-HTTP-ProxyOften used as an alternate port for web traffic
Regarding the issue of network ports
What is the difference between TCP and UDP ports?
TCP (Transmission Control Protocol) ports ensure reliable data transmission, guaranteeing that information arrives in the correct order and undergoes error checking. Conversely, UDP (User Datagram Protocol) ports prioritize enhancing data transmission speed, with less emphasis on data accuracy. Therefore, when an application requires rapid data processing, UDP is the more suitable choice, even if a small amount of data loss occurs.