What is the port number used for File Transfer Protocol (FTP)?

The port number used for File Transfer Protocol (FTP) is 21. This is the standard port designated for FTP operations and is used for both establishing a connection and for control commands. When you initiate an FTP session, the client typically connects to the server over port 21 to send commands and manage file transfers.

FTP relies on a client-server model where the client connects to the server using this specific port to request files, upload files, or manage file systems. Option 22 is associated with Secure Shell (SSH) and SFTP (SSH File Transfer Protocol), while option 25 is used for Simple Mail Transfer Protocol (SMTP), which is related to email transmission. Option 80 is the standard port for Hypertext Transfer Protocol (HTTP), used for web traffic. Therefore, 21 is unequivocally the correct answer for FTP.