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What are the TCP/IP Well Known Port Numbers (0 to 1023)

About TCP/UDP Ports

  • Port 0 to 1023: These TCP/UDP port numbers are known well-known ports. These ports are assigned to specific server sevice by the Internet Assigned Numbers Authority (IANA). For example, port 80 is used by web servers.
  • Port 1024 to 49151: These are ports that an organization, such as application developers, can register with IAMA to be used for a particular service. These should be treated as semi-reserved.
  • Port 49152 to 65535: These are port numbers used by client programs, such as a web browser. When you visit a web site, your web browser will assign that session a port number from within this range. As an application developer, you are free to use any of these ports.
Network Gear

Well-Known TCP/UDP Ports 0 to 1023

Port # Portocol Description Status
0 TCP, UDP Reserved; do not use (but is a permissible source port value if the sending process does not expect messages in response) Offical
5 TCP, UDP RJE (Remote Job Entry) Offical
7 TCP, UDP ECHO protocol Offical
9 TCP, UDP DISCARD protocol Offical
11 TCP, UDP SYSTAT protocol Offical
13 TCP, UDP DAYTIME protocol Offical
17 TCP, UDP QOTD (Quote of the Day) protocol Offical
18 TCP, UDP Message Send Protocol Offical
19 TCP, UDP CHARGEN (Character Generator) protocol Offical
20 TCP FTP Protocol (data) - port for transferring FTP data Offical
21 TCP FTP Protocol (control) - port for FTP commands and flow control Offical
22 TCP, UDP SSH (Secure Shell) - used for secure logins, file transfers (scp, sftp) and port forwarding Offical
23 TCP, UDP Telnet protocol - unencrypted text communication, remote login service Offical
25 TCP, UDP SMTP (Simple Mail Transport Protocol) - used for email routing between email servers Offical
26 TCP, UDP RSFTP - A simple FTP-like protocol Unoffical
35 TCP, UDP QMS Magicolor 2 printer Unoffical
37 TCP, UDP TIME protocol Offical
38 TCP, UDP Route Access Protocol Offical
39 TCP, UDP Resource Location Protocol Offical
41 TCP, UDP Graphics Offical
42 TCP, UDP Host Name Server/WINS Replications Offical
43 TCP WHOIS protocol Offical
49 TCP, UDP TACACS Login Host protocol Offical
53 TCP, UDP DNS (Domain Name System) Offical
57 TCP MTP, Mail Transfer Protocol Offical
67 UDP BOOTP (BootStrap Protocol) server; also used by DHCP Offical
68 UDP BOOTP (BootStrap Protocol) client; also used by DHCP Offical
69 UDP TFTP (Trivial File Transfer Protocol) Offical
70 TCP Gopher protocol Offical
79 TCP Finger protocol Offical
80 TCP HTTP (HyperText Transfer Protocol) - used for transferring web pages Offical
81 TCP Torpark - Onion routing ORport Unoffical
82 UDP Torpark - Control Port Unoffical
88 TCP Kerberos - authenticating agent Offical
102 TCP ISO-TSAP protocol/Microsoft Exchange  
107 TCP Remote Telnet Service  
109 TCP POP, Post Office Protocol, version 2  
110 TCP POP3 (Post Office Protocol version 3) - used for retrieving emails Offical
111 TCP, UDP SUNRPC protocol  
113 TCP Ident - old server identification system, still used by IRC servers to identify its users Offical
115 TCP SFTP, Simple File Transfer Protocol  
118 TCP, UDP SQL Services Offical
119 TCP NNTP (Network News Transfer Protocol) - used for retrieving newsgroups messages Offical
123 UDP NTP (Network Time Protocol) - used for time synchronization Offical
135 TCP, UDP EPMAP / Microsoft RPC Locator Service Offical
137 TCP, UDP NetBIOS NetBIOS Name Service Offical
138 TCP, UDP NetBIOS NetBIOS Datagram Service Offical
139 TCP, UDP NetBIOS NetBIOS Session Service Offical
143 TCP, UDP IMAP4 (Internet Message Access Protocol 4) - used for retrieving emails Offical
152 TCP, UDP BFTP, Background File Transfer Program  
153 TCP, UDP SGMP, Simple Gateway Monitoring Protocol  
156 TCP, UDP SQL Service Offical
157 TCP, UDP KNET VM Command Message Protocol  
158 TCP, UDP DMSP, Distributed Mail Service Protocol  
159 TCP, UDP NSS-Routing  
161 TCP, UDP SNMP (Simple Network Management Protocol) Offical
170 TCP Print-srv  
179 TCP BGP (Border Gateway Protocol) - an exterior gateway routing protocol that enables groups of routers to share routing information to ensure efficient and loop-free routes can be established. BGP is commonly used within and between ISPs. Offical
190 TCP, UDP Gateway Access Control Protocol (GACP)  
191 TCP, UDP Prospero Directory Service  
192 TCP, UDP OSU Network Monitoring System, Apple AirPort Base Station PPP status or discovery, AirPort Admin Utility or Express Assistant  
192 TCP. UDP SRMP (Spider Remote Monitoring Protocol)  
194 TCP IRC (Internet Relay Chat) Offical
201 TCP, UDP AppleTalk Routing Maintenance  
209 TCP, UDP The Quick Mail Transfer Protocol  
213 TCP, UDP IPX Offical
218 TCP, UDP MPP, Message Posting Protocol  
220 TCP, UDP IMAP, Interactive Mail AccessProtocol, version 3  
259 TCP, UDP ESRO, Efficient Short Remote Operations  
264 TCP, UDP BGMP, Border Gateway Multicast Protocol  
311 TCP Apple Server-Admin-Tool, Workgroup-Manager-Tool  
318 TCP, UDP TSP, Time Stamp Protocol  
323 TCP, UDP IMMP, Internet Message Mapping Protocol  


TCP, UDP HP OpenView HTTPs Operations Agent  
366 TCP, UDP SMTP, Simple Mail Transfer Protocol. On-Demand Mail Relay (ODMR)  
369 TCP, UDP Rpc2portmap Offical
371 TCP, UDP ClearCase albd Offical
384 TCP, UDP A Remote Network Server System  
387 TCP, UDP AURP, AppleTalk Update-Based Routing Protocol  
389 TCP, UDP LDAP (Lightweight Directory Access Protocol) Offical
401 TCP, UDP UPS Uninterruptible Power Supply Offical
411 TCP Direct Connect Hub port Unoffical
427 TCP, UDP SLP (Service Location Protocol) Offical
443 TCP HTTPS - HTTP Protocol over TLS/SSL (used for transferring web pages securely using encryption) Offical
444 TCP, UDP SNPP, Simple Network Paging Protocol  
445 TCP Microsoft-DS (Active Directory, Windows shares, Sasser worm, Agobot, Zobotworm) Offical
445 UDP Microsoft-DS SMB file sharing Offical
464 TCP, UDP Kerberos Change/Set password Offical
465 TCP SMTP over SSL - CONFLICT with registered Cisco protocol Conflict
500 TCP, UDP ISAKMP, IKE-Internet Key Exchange Offical
512 TCP exec, Remote Process Execution  
512 UDP comsat, together with biff: notifies users of new c.q. yet unread e-mail  
513 TCP Login  
513 UDP Who  
514 TCP rsh protocol - used to execute non-interactive commandline commands on a remote system and see the screen return  
514 UDP syslog protocol - used for system logging Offical
515 TCP Line Printer Daemon protocol - used in LPD printer servers  
517 TCP Talk  
518 UDP NTalk  
520 TCP efs  
520 UDP Routing - RIP Offical
513 UDP Router  
524 TCP, UDP NCP (NetWare Core Protocol) is used for a variety things such as access to primary NetWare server resources, Time Synchronization, etc. Offical
525 UDP Timed, Timeserver  
530 TCP, UDP RPC Offical
531 TCP, UDP AOL Instant Messenger, IRC  
532 TCP netnews  
533 UDP netwall, For Emergency Broadcasts  
540 TCP UUCP (Unix-to-Unix Copy Protocol)  
542 TCP, UDP commerce (Commerce Applications)  
543 TCP klogin, Kerberos login  
544 TCP kshell, Kerberos Remote Shell  
546 TCP, UDP DHCPv6 client  
547 TCP, UDP DHCPv6 server  
548 TCP AFP (Apple Filing Protocol)  
550 UDP new-rwho, new-who  
554 TCP, UDP RTSP (Real Time Streaming Protocol) Offical
556 TCP Remotefs, rfs, rfs_server  
560 UDP rmonitor, Remote Monitor  
561 UDP monitor  
561 TCP, UDP chcmd  
563 TCP, UDP NNTP protocol over TLS/SSL (NNTPS) Offical
587 TCP Email message submission (SMTP) (RFC 2476) Offical
591 TCP FileMaker 6.0 Web Sharing (HTTP Alternate, see port 80) Offical
593 TCP, UDP HTTP RPC Ep Map/Microsoft DCOM Offical
631 TCP, UDP IPP, Internet Printing Protocol  
636 TCP, UDP LDAP over SSL (encrypted transmission) Offical
639 TCP, UDP MSDP, Multicast Source Discovery Protocol  
646 TCP LDP, Label Distribution Protocol  
647 TCP DHCP Failover Protocol  
648 TCP RRP, Registry Registrar Protocol  
652 TCP DTCP, Dynamic Tunnel Configuration Protocol  
654 TCP AODV, Ad hoc On-Demand Distance Vector  
665 TCP sun-dr, Remote Dynamic Reconfiguration Unoffical
666 UDP Doom, First online FPS  
674 TCP ACAP, Application Configuration Access Protocol  
691 TCP Microsoft Exchange Routing Offical
692 TCP Hyperwave-ISP  
698 TCP OLSR, Optimized Link State Routing  
699 TCP Access Network  
700 TCP EPP, Extensible Provisioning Protocol  
701 TCP LMP, Link Management Protocol.  
702 TCP IRIS over BEEP  
706 TCP SILC, Secure Internet Live Conferencing  
711 TCP TDP, Tag Distribution Protocol  
712 TCP TBRPF, Topology Broadcast based on Reverse-Path Forwarding  
720 TCP SMQP, Simple Message Queue Protocol  
749 TCP, UDP kerberos-adm, Kerberos administration  
750 UDP Kerberos version IV  
782 TCP Conserver serial-console management server  
829 TCP CMP (Certificate Management Protocol)  
860 TCP iSCSI  
873 TCP rsync - File synchronisation protocol Offical
901 TCP Samba Web Administration Tool (SWAT) Unoffical
902   VMware Server Unoffical
911 TCP Network Console on Acid (NCA) - local tty redirection over OpenSSH  
981 TCP SofaWare Technologies Remote HTTPS management for firewall devices running embedded Checkpoint Firewall-1 software Unoffical
989 TCP, UDP FTP Protocol (data) over TLS/SSL Offical
990 TCP, UDP FTP Protocol (control) over TLS/SSL Offical
991 TCP, UDP NAS (Netnews Admin System)  
992 TCP, UDP Telnet protocol over TLS/SSL Offical
993 TCP IMAP4 over SSL (encrypted transmission) Offical
995 TCP POP3 over SSL (encrypted transmission) Offical
  • Ports 0 to 1023 are Well-Known Ports.
  • Ports 1024 to 49151 are Registered Ports (often registered by a software developer to designate a particular port for their application)
  • Ports 49152 to 65535 are Public Ports.
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