Well-known ports
The port numbers in the range from 0 to 1023 are the well-known ports. They are used by system processes that provide widely used types of network services. On Unix-like operating systems, a process must execute with superuser privileges to be able to bind a network socket to an IP address using one of the well-known ports.
Port
|
TCP
|
UDP
|
Description
|
Status
|
0
|
UDP
|
Reserved
|
Official
| |
1
|
TCP
|
UDP
|
TCP Port Service Multiplexer (TCPMUX)
|
Official
|
2
|
TCP
|
UDP
|
CompressNET[2] Management Utility[3]
|
Official
|
3
|
TCP
|
UDP
|
CompressNET[2] Compression Process[4]
|
Official
|
4
|
TCP
|
UDP
|
Unassigned
|
Official
|
5
|
TCP
|
UDP
|
Remote Job Entry
|
Official
|
7
|
TCP
|
UDP
|
Echo Protocol
|
Official
|
8
|
TCP
|
UDP
|
Unassigned
|
Official
|
9
|
TCP
|
UDP
|
Discard Protocol
|
Official
|
10
|
TCP
|
UDP
|
Unassigned
|
Official
|
11
|
TCP
|
UDP
|
Active Users (systat service)[5][6]
|
Official
|
12
|
TCP
|
UDP
|
Unassigned
|
Official
|
13
|
TCP
|
UDP
|
Daytime Protocol (RFC 867)
|
Official
|
14
|
TCP
|
UDP
|
Unassigned
|
Official
|
15
|
TCP
|
UDP
|
Previously netstat service[5]
|
Unofficial
|
16
|
TCP
|
UDP
|
Unassigned
|
Official
|
17
|
TCP
|
UDP
|
Quote of the Day
|
Official
|
18
|
TCP
|
UDP
|
Message Send Protocol
|
Official
|
19
|
TCP
|
UDP
|
Character Generator Protocol (CHARGEN)
|
Official
|
20
|
TCP
|
FTP data transfer
|
Official
| |
21
|
TCP
|
FTP control (command)
|
Official
| |
22
|
TCP
|
Secure Shell (SSH)—used for secure logins, file transfers (scp, sftp) and port forwarding
|
Official
| |
23
|
TCP
|
Telnet protocol—unencrypted text communications
|
Official
| |
24
|
TCP
|
UDP
|
Priv-mail : any private mail system.
|
Official
|
25
|
TCP
|
Simple Mail Transfer Protocol (SMTP)—used for e-mail routing between mail servers
|
Official
| |
26
|
TCP
|
UDP
|
Unassigned
|
Official
|
27
|
TCP
|
UDP
|
NSW User System FE
|
Official
|
29
|
TCP
|
UDP
|
MSG ICP
|
Official
|
33
|
TCP
|
UDP
|
Display Support Protocol
|
Official
|
35
|
TCP
|
UDP
|
Any private printer server protocol
|
Official
|
37
|
TCP
|
UDP
|
TIME protocol
|
Official
|
39
|
TCP
|
UDP
|
Resource Location Protocol[7] (RLP)—used for determining the location of higher level services from hosts on a network
|
Official
|
40
|
TCP
|
UDP
|
Unassigned
|
Official
|
42
|
TCP
|
UDP
|
ARPA Host Name Server Protocol
|
Official
|
42
|
TCP
|
UDP
|
Windows Internet Name Service
|
Unofficial
|
43
|
TCP
|
WHOIS protocol
|
Official
| |
47
|
TCP
|
UDP
|
NI FTP[7]
|
Official
|
49
|
TCP
|
UDP
|
TACACS Login Host protocol
|
Official
|
50
|
TCP
|
UDP
|
Remote Mail Checking Protocol[8]
|
Official
|
51
|
TCP
|
UDP
|
IMP Logical Address Maintenance
|
Official
|
52
|
TCP
|
UDP
|
XNS (Xerox Network Systems) Time Protocol
|
Official
|
53
|
TCP
|
UDP
|
Domain Name System (DNS)
|
Official
|
54
|
TCP
|
UDP
|
XNS (Xerox Network Systems) Clearinghouse
|
Official
|
55
|
TCP
|
UDP
|
ISI Graphics Language (ISI-GL)
|
Official
|
56
|
TCP
|
UDP
|
XNS (Xerox Network Systems) Authentication
|
Official
|
56
|
TCP
|
UDP
|
Route Access Protocol (RAP)[9]
|
Unofficial
|
57
|
TCP
|
Mail Transfer Protocol (RFC 780)
|
Official
| |
58
|
TCP
|
UDP
|
XNS (Xerox Network Systems) Mail
|
Official
|
67
|
UDP
|
Bootstrap Protocol (BOOTP) Server; also used by Dynamic Host Configuration Protocol (DHCP)
|
Official
| |
68
|
UDP
|
Bootstrap Protocol (BOOTP) Client; also used by Dynamic Host Configuration Protocol (DHCP)
|
Official
| |
69
|
UDP
|
Trivial File Transfer Protocol (TFTP)
|
Official
| |
70
|
TCP
|
Gopher protocol
|
Official
| |
71
|
TCP
|
NETRJS protocol
|
Official
| |
72
|
TCP
|
NETRJS protocol
|
Official
| |
73
|
TCP
|
NETRJS protocol
|
Official
| |
74
|
TCP
|
NETRJS protocol
|
Official
| |
79
|
TCP
|
Finger protocol
|
Official
| |
80
|
TCP
|
Hypertext Transfer Protocol (HTTP)
|
Official[10]
| |
81
|
TCP
|
Torpark—Onion routing
|
Unofficial
| |
82
|
UDP
|
Torpark—Control
|
Unofficial
| |
88
|
TCP
|
UDP
|
Kerberos—authentication system
|
Official
|
90
|
TCP
|
UDP
|
dnsix (DoD Network Security for Information Exchange) Securit Attribute Token Map
|
Official
|
90
|
TCP
|
UDP
|
PointCast (dotcom)
|
Unofficial
|
99
|
TCP
|
WIP Message protocol
|
Unofficial
| |
101
|
TCP
|
NIC host name
|
Official
| |
102
|
TCP
|
ISO-TSAP (Transport Service Access Point) Class 0 protocol[11]
|
Official
| |
104
|
TCP
|
UDP
|
ACR/NEMA Digital Imaging and Communications in Medicine
|
Official
|
105
|
TCP
|
UDP
|
CCSO Nameserver Protocol (Qi/Ph)
|
Official
|
107
|
TCP
|
Remote TELNET Service[12] protocol
|
Official
| |
108
|
TCP
|
UDP
|
SNA Gateway Access Server [1]
|
Official
|
109
|
TCP
|
Post Office Protocol v2 (POP2)
|
Official
| |
110
|
TCP
|
Post Office Protocol v3 (POP3)
|
Official
| |
111
|
TCP
|
UDP
|
ONC RPC (Sun RPC)
|
Official
|
113
|
TCP
|
ident—Authentication Service/Identification Protocol,[13] used by IRC servers to identify users
|
Official
| |
113
|
UDP
|
Authentication Service[13] (auth)
|
Official
| |
115
|
TCP
|
Simple File Transfer Protocol (SFTP)
|
Official
| |
117
|
TCP
|
UUCP Path Service
|
Official
| |
118
|
TCP
|
UDP
|
SQL (Structured Query Language) Services
|
Official
|
119
|
TCP
|
Network News Transfer Protocol (NNTP)—retrieval of newsgroup messages
|
Official
| |
123
|
UDP
|
Network Time Protocol (NTP)—used for time synchronization
|
Official
| |
126
|
TCP
|
UDP
|
Formerly Unisys Unitary Login, renamed by Unisys to NXEdit. Used by Unisys Programmer's Workbench for Clearpath MCP, an IDE for Unisys MCP software development
|
Official
|
135
|
TCP
|
UDP
|
DCE endpoint resolution
|
Official
|
135
|
TCP
|
UDP
|
Microsoft EPMAP (End Point Mapper), also known as DCE/RPC Locator service,[14] used to remotely manage services including DHCP server, DNS server and WINS. Also used by DCOM
|
Unofficial
|
137
|
TCP
|
UDP
|
NetBIOS NetBIOS Name Service
|
Official
|
138
|
TCP
|
UDP
|
NetBIOS NetBIOS Datagram Service
|
Official
|
139
|
TCP
|
UDP
|
NetBIOS NetBIOS Session Service
|
Official
|
143
|
TCP
|
Internet Message Access Protocol (IMAP)—management of email messages
|
Official
| |
152
|
TCP
|
UDP
|
Background File Transfer Program (BFTP)[15]
|
Official
|
153
|
TCP
|
UDP
|
SGMP, Simple Gateway Monitoring Protocol
|
Official
|
156
|
TCP
|
UDP
|
SQL Service
|
Official
|
158
|
TCP
|
UDP
|
DMSP, Distributed Mail Service Protocol[16]
|
Unofficial
|
161
|
UDP
|
Simple Network Management Protocol (SNMP)
|
Official
| |
162
|
TCP
|
UDP
|
Simple Network Management Protocol Trap (SNMPTRAP)[17]
|
Official
|
170
|
TCP
|
Print-srv, Network PostScript
|
Official
| |
175
|
TCP
|
VMNET (IBM z/VM, z/OS & z/VSE - Network Job Entry(NJE))
|
Official
| |
177
|
TCP
|
UDP
|
X Display Manager Control Protocol (XDMCP)
|
Official
|
179
|
TCP
|
BGP (Border Gateway Protocol)
|
Official
| |
194
|
TCP
|
UDP
|
Internet Relay Chat (IRC)
|
Official
|
199
|
TCP
|
UDP
|
SMUX, SNMP Unix Multiplexer
|
Official
|
201
|
TCP
|
UDP
|
AppleTalk Routing Maintenance
|
Official
|
209
|
TCP
|
UDP
|
The Quick Mail Transfer Protocol
|
Official
|
210
|
TCP
|
UDP
|
ANSI Z39.50
|
Official
|
213
|
TCP
|
UDP
|
Internetwork Packet Exchange (IPX)
|
Official
|
218
|
TCP
|
UDP
|
Message posting protocol (MPP)
|
Official
|
220
|
TCP
|
UDP
|
Internet Message Access Protocol (IMAP), version 3
|
Official
|
259
|
TCP
|
UDP
|
ESRO, Efficient Short Remote Operations
|
Official
|
264
|
TCP
|
UDP
|
BGMP, Border Gateway Multicast Protocol
|
Official
|
280
|
TCP
|
UDP
|
http-mgmt
|
Official
|
308
|
TCP
|
Novastor Online Backup
|
Official
| |
311
|
TCP
|
Mac OS X Server Admin (officially AppleShare IP Web administration)
|
Official
| |
318
|
TCP
|
UDP
|
PKIX TSP, Time Stamp Protocol
|
Official
|
319
|
UDP
|
Precision time protocol event messages
|
Official
| |
320
|
UDP
|
Precision time protocol general messages
|
Official
| |
350
|
TCP
|
UDP
|
MATIP-Type A, Mapping of Airline Traffic over Internet Protocol
|
Official
|
351
|
TCP
|
UDP
|
MATIP-Type B, Mapping of Airline Traffic over Internet Protocol
|
Official
|
366
|
TCP
|
UDP
|
ODMR, On-Demand Mail Relay
|
Official
|
369
|
TCP
|
UDP
|
Rpc2portmap
|
Official
|
370
|
TCP
|
codaauth2—Coda authentication server
|
Official
| |
370
|
UDP
|
codaauth2—Coda authentication server
|
Official
| |
370
|
UDP
|
securecast1—Outgoing packets to NAI's servers [18][dead link]
|
Unofficial
| |
371
|
TCP
|
UDP
|
ClearCase albd
|
Official
|
383
|
TCP
|
UDP
|
HP data alarm manager
|
Official
|
384
|
TCP
|
UDP
|
A Remote Network Server System
|
Official
|
387
|
TCP
|
UDP
|
AURP, AppleTalk Update-based Routing Protocol[19]
|
Official
|
389
|
TCP
|
UDP
|
Lightweight Directory Access Protocol (LDAP)
|
Official
|
399
|
TCP
|
UDP
|
Digital Equipment Corporation DECnet (Phase V+) over TCP/IP
|
Official
|
401
|
TCP
|
UDP
|
UPS Uninterruptible Power Supply
|
Official
|
427
|
TCP
|
UDP
|
Service Location Protocol (SLP)
|
Official
|
443
|
TCP
|
HTTPS (Hypertext Transfer Protocol over SSL/TLS)
|
Official
| |
444
|
TCP
|
UDP
|
SNPP, Simple Network Paging Protocol (RFC 1568)
|
Official
|
445
|
TCP
|
Microsoft-DS Active Directory, Windows shares
|
Official
| |
445
|
TCP
|
Microsoft-DS SMB file sharing
|
Official
| |
464
|
TCP
|
UDP
|
Kerberos Change/Set password
|
Official
|
465
|
TCP
|
URL Rendesvous Directory for SSM (Cisco protocol)
|
Official
| |
475
|
TCP
|
UDP
|
tcpnethaspsrv (Aladdin Knowledge Systems Hasp services, TCP/IP version)
|
Official
|
497
|
TCP
|
Dantz Retrospect
|
Official
| |
500
|
UDP
|
Internet Security Association and Key Management Protocol (ISAKMP)
|
Official
| |
502
|
TCP
|
UDP
|
Modbus, Protocol
|
Unofficial
|
504
|
TCP
|
UDP
|
Citadel—multiservice protocol for dedicated clients for the Citadel groupware system
|
Official
|
512
|
TCP
|
Rexec, Remote Process Execution
|
Official
| |
512
|
UDP
|
comsat, together with biff
|
Official
| |
513
|
TCP
|
rlogin
|
Official
| |
513
|
UDP
|
Who[20]
|
Official
| |
514
|
TCP
|
Shell—used to execute non-interactive commands on a remote system (Remote Shell, rsh, remsh)
|
Official
| |
514
|
UDP
|
Syslog—used for system logging
|
Official
| |
515
|
TCP
|
Line Printer Daemon—print service
|
Official
| |
517
|
UDP
|
Talk
|
Official
| |
518
|
UDP
|
NTalk
|
Official
| |
520
|
TCP
|
efs, extended file name server
|
Official
| |
520
|
UDP
|
Routing Information Protocol (RIP)
|
Official
| |
524
|
TCP
|
UDP
|
NetWare Core Protocol (NCP) is used for a variety things such as access to primary NetWare server resources, Time Synchronization, etc.
|
Official
|
525
|
UDP
|
Timed, Timeserver
|
Official
| |
530
|
TCP
|
UDP
|
RPC
|
Official
|
531
|
TCP
|
UDP
|
AOL Instant Messenger
|
Unofficial
|
532
|
TCP
|
netnews
|
Official
| |
533
|
UDP
|
netwall, For Emergency Broadcasts
|
Official
| |
540
|
TCP
|
UUCP (Unix-to-Unix Copy Protocol)
|
Official
| |
542
|
TCP
|
UDP
|
commerce (Commerce Applications)
|
Official
|
543
|
TCP
|
klogin, Kerberos login
|
Official
| |
544
|
TCP
|
kshell, Kerberos Remote shell
|
Official
| |
545
|
TCP
|
OSIsoft PI (VMS), OSISoft PI Server Client Access
|
Unofficial
| |
546
|
TCP
|
UDP
|
DHCPv6 client
|
Official
|
547
|
TCP
|
UDP
|
DHCPv6 server
|
Official
|
548
|
TCP
|
Apple Filing Protocol (AFP) over TCP
|
Official
| |
550
|
TCP
|
UDP
|
new-rwho, new-who[20]
|
Official
|
554
|
TCP
|
UDP
|
Real Time Streaming Protocol (RTSP)
|
Official
|
556
|
TCP
|
Remotefs, RFS, rfs_server
|
Official
| |
560
|
UDP
|
rmonitor, Remote Monitor
|
Official
| |
561
|
UDP
|
monitor
|
Official
| |
563
|
TCP
|
UDP
|
NNTP protocol over TLS/SSL (NNTPS)
|
Official
|
587
|
TCP
|
e-mail message submission[21] (SMTP)
|
Official
| |
591
|
TCP
|
FileMaker 6.0 (and later) Web Sharing (HTTP Alternate, also see port 80)
|
Official
| |
593
|
TCP
|
UDP
|
HTTP RPC Ep Map, Remote procedure call over Hypertext Transfer Protocol, often used by Distributed Component Object Model services and Microsoft Exchange Server
|
Official
|
604
|
TCP
|
TUNNEL profile,[22] a protocol for BEEP peers to form an application layer tunnel
|
Official
| |
623
|
UDP
|
ASF Remote Management and Control Protocol (ASF-RMCP)
|
Official
| |
631
|
TCP
|
UDP
|
Internet Printing Protocol (IPP)
|
Official
|
631
|
TCP
|
UDP
|
Common Unix Printing System (CUPS)
|
Unofficial
|
635
|
TCP
|
UDP
|
RLZ DBase
|
Official
|
636
|
TCP
|
UDP
|
Lightweight Directory Access Protocol over TLS/SSL (LDAPS)
|
Official
|
639
|
TCP
|
UDP
|
MSDP, Multicast Source Discovery Protocol
|
Official
|
641
|
TCP
|
UDP
|
SupportSoft Nexus Remote Command (control/listening): A proxy gateway connecting remote control traffic
|
Official
|
646
|
TCP
|
UDP
|
LDP, Label Distribution Protocol, a routing protocol used in MPLS networks
|
Official
|
647
|
TCP
|
DHCP Failover protocol[23]
|
Official
| |
648
|
TCP
|
RRP (Registry Registrar Protocol)[24]
|
Official
| |
651
|
TCP
|
UDP
|
IEEE-MMS
|
Official
|
653
|
TCP
|
UDP
|
SupportSoft Nexus Remote Command (data): A proxy gateway connecting remote control traffic
|
Official
|
654
|
TCP
|
Media Management System (MMS) Media Management Protocol (MMP)[25]
|
Official
| |
657
|
TCP
|
UDP
|
IBM RMC (Remote monitoring and Control) protocol, used by System p5 AIX Integrated Virtualization Manager (IVM)[26] and Hardware Management Consoleto connect managed logical partitions (LPAR) to enable dynamic partition reconfiguration
|
Official
|
660
|
TCP
|
Mac OS X Server administration
|
Official
| |
666
|
UDP
|
Doom, first online first-person shooter
|
Official
| |
666
|
TCP
|
airserv-ng, aircrack-ng's server for remote-controlling wireless devices
|
Unofficial
| |
674
|
TCP
|
ACAP (Application Configuration Access Protocol)
|
Official
| |
688
|
TCP
|
UDP
|
REALM-RUSD (ApplianceWare Server Appliance Management Protocol)
|
Official
|
691
|
TCP
|
MS Exchange Routing
|
Official
| |
694
|
TCP
|
UDP
|
Linux-HA High availability Heartbeat
|
Official
|
695
|
TCP
|
IEEE-MMS-SSL (IEEE Media Management System over SSL)[27]
|
Official
| |
698
|
UDP
|
OLSR (Optimized Link State Routing)
|
Official
| |
700
|
TCP
|
EPP (Extensible Provisioning Protocol), a protocol for communication between domain name registries and registrars (RFC 5734)
|
Official
| |
701
|
TCP
|
LMP (Link Management Protocol (Internet)),[28] a protocol that runs between a pair of nodes and is used to manage traffic engineering (TE) links
|
Official
| |
702
|
TCP
|
IRIS[29][30] (Internet Registry Information Service) over BEEP (Blocks Extensible Exchange Protocol)[31] (RFC 3983)
|
Official
| |
706
|
TCP
|
Secure Internet Live Conferencing (SILC)
|
Official
| |
711
|
TCP
|
Cisco Tag Distribution Protocol[32][33][34]—being replaced by the MPLS Label Distribution Protocol[35]
|
Official
| |
712
|
TCP
|
Topology Broadcast based on Reverse-Path Forwarding routing protocol (TBRPF) (RFC 3684)
|
Official
| |
749
|
TCP
|
UDP
|
Kerberos (protocol) administration
|
Official
|
750
|
UDP
|
kerberos-iv, Kerberos version IV
|
Official
| |
751
|
TCP
|
UDP
|
kerberos_master, Kerberos authentication
|
Unofficial
|
752
|
UDP
|
passwd_server, Kerberos Password (kpasswd) server
|
Unofficial
| |
753
|
TCP
|
Reverse Routing Header (rrh)[36]
|
Official
| |
753
|
UDP
|
Reverse Routing Header (rrh)
|
Official
| |
753
|
UDP
|
userreg_server, Kerberos userreg server
|
Unofficial
| |
754
|
TCP
|
tell send
|
Official
| |
754
|
TCP
|
krb5_prop, Kerberos v5 slave propagation
|
Unofficial
| |
754
|
UDP
|
tell send
|
Official
| |
760
|
TCP
|
UDP
|
krbupdate [kreg], Kerberos registration
|
Unofficial
|
782
|
TCP
|
Conserver serial-console management server
|
Unofficial
| |
783
|
TCP
|
SpamAssassin spamd daemon
|
Unofficial
| |
808
|
TCP
|
Microsoft Net.TCP Port Sharing Service
|
Official
| |
829
|
TCP
|
Certificate Management Protocol[37]
|
Unofficial
| |
843
|
TCP
|
Adobe Flash[38]
|
Official
| |
847
|
TCP
|
DHCP Failover protocol
|
Official
| |
848
|
TCP
|
UDP
|
Group Domain Of Interpretation (GDOI) protocol
|
Official
|
860
|
TCP
|
iSCSI (RFC 3720)
|
Official
| |
861
|
TCP
|
UDP
|
OWAMP control (RFC 4656)
|
Official
|
862
|
TCP
|
UDP
|
TWAMP control (RFC 5357)
|
Official
|
873
|
TCP
|
rsync file synchronization protocol
|
Official
| |
888
|
TCP
|
cddbp, CD DataBase (CDDB) protocol (CDDBP)
|
Unofficial
| |
897
|
TCP
|
UDP
|
Brocade SMI-S RPC
|
Unofficial
|
898
|
TCP
|
UDP
|
Brocade SMI-S RPC SSL
|
Unofficial
|
901
|
TCP
|
Samba Web Administration Tool (SWAT)
|
Unofficial
| |
901
|
TCP
|
VMware Virtual Infrastructure Client (UDP from server being managed to management console)
|
Unofficial
| |
901
|
UDP
|
VMware Virtual Infrastructure Client (UDP from server being managed to management console)
|
Unofficial
| |
902
|
TCP
|
ideafarm-door
|
Official
| |
902
|
TCP
|
VMware Server Console (TCP from management console to server being Managed)
|
Unofficial
| |
902
|
UDP
|
ideafarm-door
|
Official
| |
902
|
UDP
|
VMware Server Console (UDP from server being managed to management console)
|
Unofficial
| |
903
|
TCP
|
VMware Remote Console [39]
|
Unofficial
| |
904
|
TCP
|
VMware Server Alternate (if 902 is in use, i.e. SUSE linux)
|
Unofficial
| |
911
|
TCP
|
Network Console on Acid (NCA)—local tty redirection over OpenSSH
|
Unofficial
| |
944
|
UDP
|
Network File System (protocol) Service
|
Unofficial
| |
953
|
TCP
|
UDP
|
Domain Name System (DNS) RNDC Service
|
Unofficial
|
973
|
UDP
|
Network File System (protocol) over IPv6 Service
|
Unofficial
| |
981
|
TCP
|
SofaWare Technologies Remote HTTPS management for firewall devices running embedded Check Point FireWall-1 software
|
Unofficial
| |
987
|
TCP
|
Microsoft Corporation Microsoft Windows SBS SharePoint
|
Unofficial
| |
989
|
TCP
|
UDP
|
FTPS Protocol (data): FTP over TLS/SSL
|
Official
|
990
|
TCP
|
UDP
|
FTPS Protocol (control): FTP over TLS/SSL
|
Official
|
991
|
TCP
|
UDP
|
NAS (Netnews Administration System)[40]
|
Official
|
992
|
TCP
|
UDP
|
TELNET protocol over TLS/SSL
|
Official
|
993
|
TCP
|
Internet Message Access Protocol over SSL (IMAPS)
|
Official
| |
995
|
TCP
|
Post Office Protocol 3 over TLS/SSL (POP3S)
|
Official
| |
999
|
TCP
|
ScimoreDB Database System
|
Unofficial
| |
1002
|
TCP
|
Opsware agent (aka cogbot)
|
Unofficial
| |
1023
|
TCP
|
UDP
|
Reserved[1]
|
Official
|
