List of TCP and UDP port numbers
Well-known ports
The port numbers in the range from 0 to 1023 are the well-known ports or system ports. They are used by system processes that provide widely used types of network services.

List of TCP and UDP port numbers

Section Title: Well-known ports
Table Section Text: The port numbers in the range from 0 to 1023 are the well-known ports or system ports. They are used by system processes that provide widely used types of network services.

Port	TCP	UDP	IANA status	Description

0	Reserved	Reserved	Official

N/A	N/A	Unofficial	In programming APIs (not in communication between hosts), requests a system-allocated (dynamic) port

1	Yes	Assigned	Official	TCP Port Service Multiplexer (TCPMUX). Historic.

5	Assigned	Assigned	Official	Remote Job Entry was historically using socket 5 in its old socket form, while MIB PIM has identified it as TCP/5 and IANA has assigned both TCP and UDP 5 to it.

7	Yes	Yes	Official	Echo Protocol

9	Yes, and SCTP	Yes	Official	Discard Protocol

No	Yes	Unofficial	Wake-on-LAN

11	Yes	Yes	Official	Active Users (systat service)

13	Yes	Yes	Official	Daytime Protocol

15	Yes	No	Unofficial	Previously netstat service

17	Yes	Yes	Official	Quote of the Day (QOTD)

18	Yes	Yes	Official	Message Send Protocol

19	Yes	Yes	Official	Character Generator Protocol (CHARGEN)

20	Yes, and SCTP	Assigned	Official	File Transfer Protocol (FTP) data transfer

21	Yes, and SCTP	Assigned	Official	File Transfer Protocol (FTP) control (command)

22	Yes, and SCTP	Assigned	Official	Secure Shell (SSH), secure logins, file transfers (scp, sftp) and port forwarding

23	Yes	Assigned	Official	Telnet protocol—unencrypted text communications

25	Yes	Assigned	Official	Simple Mail Transfer Protocol (SMTP), used for email routing between mail servers

37	Yes	Yes	Official	Time Protocol

42	Assigned	Yes	Official	Host Name Server Protocol

43	Yes	Assigned	Official	WHOIS protocol

47	Reserved	Reserved	Official

49	Yes	Yes	Official	TACACS Login Host protocol. TACACS+, still in draft which is an improved but distinct version of TACACS, only uses TCP 49.

51	Reserved	Reserved	Official	Historically used for Interface Message Processor logical address management, entry has been removed by IANA on 2013-05-25

52	Assigned	Assigned	Official	Xerox Network Systems (XNS) Time Protocol. Despite this port being assigned by IANA, the service is meant to work on SPP (ancestor of IPX/SPX), instead of TCP/IP.

53	Yes	Yes	Official	Domain Name System (DNS)

54	Assigned	Assigned	Official	Xerox Network Systems (XNS) Clearinghouse (Name Server). Despite this port being assigned by IANA, the service is meant to work on SPP (ancestor of IPX/SPX), instead of TCP/IP.

56	Assigned	Assigned	Official	Xerox Network Systems (XNS) Authentication Protocol. Despite this port being assigned by IANA, the service is meant to work on SPP (ancestor of IPX/SPX), instead of TCP/IP.

58	Assigned	Assigned	Official	Xerox Network Systems (XNS) Mail. Despite this port being assigned by IANA, the service is meant to work on SPP (ancestor of IPX/SPX), instead of TCP/IP.

61	Reserved	Reserved	Official	Historically assigned to the NIFTP-Based Mail protocol, but was never documented in the related IEN. The port number entry was removed from IANA's registry on 2017-05-18.

67	Assigned	Yes	Official	Bootstrap Protocol (BOOTP) server; also used by Dynamic Host Configuration Protocol (DHCP)

68	Assigned	Yes	Official	Bootstrap Protocol (BOOTP) client; also used by Dynamic Host Configuration Protocol (DHCP)

69	Assigned	Yes	Official	Trivial File Transfer Protocol (TFTP)

70	Yes	Assigned	Official	Gopher protocol

71–74	Yes	Yes	Official	NETRJS protocol

79	Yes	Assigned	Official	Finger protocol

80	Yes, and SCTP	Assigned	Official	Hypertext Transfer Protocol (HTTP)

No	Yes	Unofficial	QUIC, a transport protocol over UDP (still in draft as of March 2019), using stream multiplexing, encryption by default with TLS, and currently supporting HTTP/2.

81	Yes	Unofficial	TorPark onion routing[verification needed]

82	Yes	Unofficial	TorPark control[verification needed]

88	Yes	Assigned	Official	Kerberos authentication system

90	Yes	Yes	Unofficial	PointCast (dotcom)

101	Yes	Assigned	Official	NIC host name

102	Yes	Assigned	Official	ISO Transport Service Access Point (TSAP) Class 0 protocol;

104	Yes	Yes	Official	Digital Imaging and Communications in Medicine (DICOM; also port 11112)

105	Yes	Yes	Official	CCSO Nameserver

107	Yes	Yes	Official	Remote User Telnet Service (RTelnet)

108	Yes	Yes	Official	IBM Systems Network Architecture (SNA) gateway access server

109	Yes	Assigned	Official	Post Office Protocol, version 2 (POP2)

110	Yes	Assigned	Official	Post Office Protocol, version 3 (POP3)

111	Yes	Yes	Official	Open Network Computing Remote Procedure Call (ONC RPC, sometimes referred to as Sun RPC)

113	Yes	No	Official	Ident, authentication service/identification protocol, used by IRC servers to identify users

Yes	Assigned	Official	Authentication Service (auth), the predecessor to identification protocol. Used to determine a user's identity of a particular TCP connection.

115	Yes	Assigned	Official	Simple File Transfer Protocol

117	Yes	Yes	Official	UUCP Mapping Project (path service)

118	Yes	Yes	Official	Structured Query Language (SQL) Services[jargon]

119	Yes	Assigned	Official	Network News Transfer Protocol (NNTP), retrieval of newsgroup messages

123	Assigned	Yes	Official	Network Time Protocol (NTP), used for time synchronization

126	Yes	Yes	Official	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

135	Yes	Yes	Official	DCE endpoint resolution

Yes	Yes	Official	Microsoft EPMAP (End Point Mapper), also known as DCE/RPC Locator service, used to remotely manage services including DHCP server, DNS server and WINS.

137	Yes	Yes	Official	NetBIOS Name Service, used for name registration and resolution

138	Assigned	Yes	Official	NetBIOS Datagram Service

139	Yes	Assigned	Official	NetBIOS Session Service

143	Yes	Assigned	Official	Internet Message Access Protocol (IMAP), management of electronic mail messages on a server

152	Yes	Yes	Official	Background File Transfer Program (BFTP)[importance?]

153	Yes	Yes	Official	Simple Gateway Monitoring Protocol (SGMP), a protocol for remote inspection and alteration of gateway management information

156	Yes	Yes	Official	Structured Query Language (SQL) Service[jargon]

158	Yes	Yes	Official	Distributed Mail System Protocol (DMSP, sometimes referred to as Pcmail)[importance?]

161	Assigned	Yes	Official	Simple Network Management Protocol (SNMP)

162	Yes	Yes	Official	Simple Network Management Protocol Trap (SNMPTRAP)

170	Yes	Yes	Official	Network PostScript print server

177	Yes	Yes	Official	X Display Manager Control Protocol (XDMCP), used for remote logins to an X Display Manager server

179	Yes, and SCTP	Assigned	Official	Border Gateway Protocol (BGP), used to exchange routing and reachability information among autonomous systems (AS) on the Internet

194	Yes	Yes	Official	Internet Relay Chat (IRC)

201	Yes	Yes	Official	AppleTalk Routing Maintenance

209	Yes	Assigned	Official	Quick Mail Transfer Protocol

210	Yes	Yes	Official	ANSI Z39.50

213	Yes	Yes	Official	Internetwork Packet Exchange (IPX)

218	Yes	Yes	Official	Message posting protocol (MPP)

220	Yes	Yes	Official	Internet Message Access Protocol (IMAP), version 3

225–241	Reserved	Reserved	Official

249–255	Reserved	Reserved	Official

259	Yes	Yes	Official	Efficient Short Remote Operations (ESRO)

262	Yes	Yes	Official	Arcisdms

264	Yes	Yes	Official	Border Gateway Multicast Protocol (BGMP)

280	Yes	Yes	Official	http-mgmt

300	Yes	Unofficial	ThinLinc Web Access

308	Yes	Official	Novastor Online Backup

311	Yes	Assigned	Official	Mac OS X Server Admin (officially AppleShare IP Web administration)

318	Yes	Yes	Official	PKIX Time Stamp Protocol (TSP)

319	Yes	Official	Precision Time Protocol (PTP) event messages

320	Yes	Official	Precision Time Protocol (PTP) general messages

350	Yes	Yes	Official	Mapping of Airline Traffic over Internet Protocol (MATIP) type A

351	Yes	Yes	Official	MATIP type B

356	Yes	Yes	Official	cloanto-net-1 (used by Cloanto Amiga Explorer and VMs)

366	Yes	Yes	Official	On-Demand Mail Relay (ODMR)

369	Yes	Yes	Official	Rpc2portmap

370	Yes	Yes	Official	codaauth2, Coda authentication server

Yes	Official	securecast1, outgoing packets to NAI's SecureCast serversAs of 2000

371	Yes	Yes	Official	ClearCase albd

383	Yes	Yes	Official	HP data alarm manager

384	Yes	Yes	Official	A Remote Network Server System

387	Yes	Yes	Official	AURP (AppleTalk Update-based Routing Protocol)

388	Yes	Assigned	Official	Unidata LDM near real-time data distribution protocol

389	Yes	Assigned	Official	Lightweight Directory Access Protocol (LDAP)

399	Yes	Yes	Official	Digital Equipment Corporation DECnet (Phase V+) over TCP/IP

401	Yes	Yes	Official	Uninterruptible power supply (UPS)

427	Yes	Yes	Official	Service Location Protocol (SLP)

433	Yes	Yes	Official	NNSP, part of Network News Transfer Protocol

434	Yes	Yes	Official	Mobile IP Agent (RFC 5944)

443	Yes, and SCTP	Assigned	Official	Hypertext Transfer Protocol over TLS/SSL (HTTPS)

No	Yes	Unofficial	Quick UDP Internet Connections (QUIC), a transport protocol over UDP (still in draft as of July 2018), using stream multiplexing, encryption by default with TLS, and currently supporting HTTP/2.

444	Yes	Yes	Official	Simple Network Paging Protocol (SNPP), RFC 1568

445	Yes	Yes	Official	Microsoft-DS (Directory Services) Active Directory, Windows shares

Yes	Assigned	Official	Microsoft-DS (Directory Services) SMB file sharing

464	Yes	Yes	Official	Kerberos Change/Set password

465	Yes	No	Official	URL Rendezvous Directory for SSM (Cisco protocol)[importance?]

Yes	No	Official	Authenticated SMTP over TLS/SSL (SMTPS)

475	Yes	Yes	Official	tcpnethaspsrv, Aladdin Knowledge Systems Hasp services

491	Yes	Unofficial	GO-Global remote access and application publishing software

497	Yes	Yes	Official	Retrospect

500	Assigned	Yes	Official	Internet Security Association and Key Management Protocol (ISAKMP) / Internet Key Exchange (IKE)

502	Yes	Yes	Official	Modbus Protocol

504	Yes	Yes	Official	Citadel, multiservice protocol for dedicated clients for the Citadel groupware system

510	Yes	Yes	Official	FirstClass Protocol (FCP), used by FirstClass client/server groupware system

512	Yes	Official	Rexec, Remote Process Execution

Yes	Official	comsat, together with biff[disambiguation needed]

513	Yes	Official	rlogin

Yes	Official	Who

514	Yes	Official	Remote Shell, used to execute non-interactive commands on a remote system (Remote Shell, rsh, remsh)

No	Yes	Official	Syslog, used for system logging

515	Yes	Assigned	Official	Line Printer Daemon (LPD), print service

517	Yes	Official	Talk

518	Yes	Official	NTalk

520	Yes	Official	efs, extended file name server

Yes	Official	Routing Information Protocol (RIP)

521	Yes	Official	Routing Information Protocol Next Generation (RIPng)

524	Yes	Yes	Official	NetWare Core Protocol (NCP) is used for a variety things such as access to primary NetWare server resources, Time Synchronization, etc.

525	Yes	Official	Timed, Timeserver

530	Yes	Yes	Official	Remote procedure call (RPC)

532	Yes	Assigned	Official	netnews

533	Yes	Official	netwall, For Emergency Broadcasts

540	Yes	Official	Unix-to-Unix Copy Protocol (UUCP)

542	Yes	Yes	Official	commerce (Commerce Applications)

543	Yes	Official	klogin, Kerberos login

544	Yes	Official	kshell, Kerberos Remote shell

546	Yes	Yes	Official	DHCPv6 client

547	Yes	Yes	Official	DHCPv6 server

548	Yes	Assigned	Official	Apple Filing Protocol (AFP) over TCP

550	Yes	Yes	Official	new-rwho, new-who

554	Yes	Yes	Official	Real Time Streaming Protocol (RTSP)

556	Yes	Official	Remotefs, RFS, rfs_server

560	Yes	Official	rmonitor, Remote Monitor

561	Yes	Official	monitor

563	Yes	Yes	Official	NNTP over TLS/SSL (NNTPS)

564	Yes	Unofficial	9P (Plan 9)

585	Port 993	?	Unofficial	Legacy use of Internet Message Access Protocol over TLS/SSL (IMAPS), now in use at port 993.

587	Yes	Assigned	Official	email message submission (SMTP)

591	Yes	Official	FileMaker 6.0 (and later) Web Sharing (HTTP Alternate, also see port 80)

593	Yes	Yes	Official	HTTP RPC Ep Map, Remote procedure call over Hypertext Transfer Protocol, often used by Distributed Component Object Model services and Microsoft Exchange Server

601	Yes	Official	Reliable Syslog Service — used for system logging

604	Yes	Official	TUNNEL profile, a protocol for BEEP peers to form an application layer tunnel

623	Yes	Official	ASF Remote Management and Control Protocol (ASF-RMCP) & IPMI Remote Management Protocol

625	Yes	No	Unofficial	Open Directory Proxy (ODProxy)

631	Yes	Yes	Official	Internet Printing Protocol (IPP)

Yes	Yes	Unofficial	Common Unix Printing System (CUPS) administration console (extension to IPP)

635	Yes	Yes	Official	RLZ DBase

636	Yes	Assigned	Official	Lightweight Directory Access Protocol over TLS/SSL (LDAPS)

639	Yes	Yes	Official	MSDP, Multicast Source Discovery Protocol

641	Yes	Yes	Official	SupportSoft Nexus Remote Command (control/listening), a proxy gateway connecting remote control traffic

643	Yes	Yes	Official	SANity

646	Yes	Yes	Official	Label Distribution Protocol (LDP), a routing protocol used in MPLS networks

647	Yes	Official	DHCP Failover protocol

648	Yes	Official	Registry Registrar Protocol (RRP)

651	Yes	Yes	Official	IEEE-MMS

653	Yes	Yes	Official	SupportSoft Nexus Remote Command (data), a proxy gateway connecting remote control traffic

654	Yes	Official	Media Management System (MMS) Media Management Protocol (MMP)

655	Yes	Yes	Official	Tinc VPN daemon

657	Yes	Yes	Official	IBM RMC (Remote monitoring and Control) protocol, used by System p5 AIX Integrated Virtualization Manager (IVM) and Hardware Management Console to connect managed logical partitions (LPAR) to enable dynamic partition reconfiguration

660	Yes	Assigned	Official	Mac OS X Server administration, version 10.4 and earlier

666	Yes	Yes	Official	Doom, first online first-person shooter

Yes	Unofficial	airserv-ng, aircrack-ng's server for remote-controlling wireless devices

674	Yes	Official	Application Configuration Access Protocol (ACAP)

688	Yes	Yes	Official	REALM-RUSD (ApplianceWare Server Appliance Management Protocol)

690	Yes	Yes	Official	Velneo Application Transfer Protocol (VATP)

691	Yes	Official	MS Exchange Routing

694	Yes	Yes	Official	Linux-HA high-availability heartbeat

695	Yes	Official	IEEE Media Management System over SSL (IEEE-MMS-SSL)

698	Yes	Official	Optimized Link State Routing (OLSR)

700	Yes	Official	Extensible Provisioning Protocol (EPP), a protocol for communication between domain name registries and registrars (RFC 5734)

701	Yes	Official	Link Management Protocol (LMP), a protocol that runs between a pair of nodes and is used to manage traffic engineering (TE) links

702	Yes	Official	IRIS (Internet Registry Information Service) over BEEP (Blocks Extensible Exchange Protocol) (RFC 3983)

706	Yes	Official	Secure Internet Live Conferencing (SILC)

711	Yes	Official	Cisco Tag Distribution Protocol—being replaced by the MPLS Label Distribution Protocol

712	Yes	Official	Topology Broadcast based on Reverse-Path Forwarding routing protocol (TBRPF; RFC 3684)

749	Yes	Yes	Official	Kerberos (protocol) administration

750	Yes	Official	kerberos-iv, Kerberos version IV

751	Yes	Yes	Unofficial	kerberos_master, Kerberos authentication

752	Yes	Unofficial	passwd_server, Kerberos password (kpasswd) server

753	Yes	Yes	Official	Reverse Routing Header (RRH)

Yes	Unofficial	userreg_server, Kerberos userreg server

754	Yes	Yes	Official	tell send

Yes	Unofficial	krb5_prop, Kerberos v5 slave propagation

760	Yes	Yes	Unofficial	krbupdate [kreg], Kerberos registration

782	Yes	Unofficial	Conserver serial-console management server

783	Yes	Unofficial	SpamAssassin spamd daemon

800	Yes	Yes	Official	mdbs-daemon

808	Yes	Unofficial	Microsoft Net.TCP Port Sharing Service

829	Yes	Assigned	Official	Certificate Management Protocol

830	Yes	Yes	Official	NETCONF over SSH

831	Yes	Yes	Official	NETCONF over BEEP

832	Yes	Yes	Official	NETCONF for SOAP over HTTPS

833	Yes	Yes	Official	NETCONF for SOAP over BEEP

843	Yes	Unofficial	Adobe Flash

847	Yes	Official	DHCP Failover protocol

848	Yes	Yes	Official	Group Domain Of Interpretation (GDOI) protocol

853	Yes	Yes	Official	DNS over TLS (RFC 7858)

860	Yes	Official	iSCSI (RFC 3720)

861	Yes	Yes	Official	OWAMP control (RFC 4656)

862	Yes	Yes	Official	TWAMP control (RFC 5357)

873	Yes	Official	rsync file synchronization protocol

888	Yes	Unofficial	cddbp, CD DataBase (CDDB) protocol (CDDBP)

Yes	Unofficial	IBM Endpoint Manager Remote Control

897	Yes	Yes	Unofficial	Brocade SMI-S RPC

898	Yes	Yes	Unofficial	Brocade SMI-S RPC SSL

902	Yes	Yes	Unofficial	VMware ESXi

903	Yes	Unofficial	VMware ESXi

953	Yes	Reserved	Official	BIND remote name daemon control (RNDC)

981	Yes	Unofficial	Remote HTTPS management for firewall devices running embedded Check Point VPN-1 software

987	Yes	Unofficial	Microsoft Remote Web Workplace, a feature of Windows Small Business Server

989	Yes	Yes	Official	FTPS Protocol (data), FTP over TLS/SSL

990	Yes	Yes	Official	FTPS Protocol (control), FTP over TLS/SSL

991	Yes	Yes	Official	Netnews Administration System (NAS)

992	Yes	Yes	Official	Telnet protocol over TLS/SSL

993	Yes	Assigned	Official	Internet Message Access Protocol over TLS/SSL (IMAPS)

994	Reserved	Reserved	Official

Maybe	Maybe	Unofficial	Internet Relay Chat over TLS/SSL (IRCS). Previously assigned, but not used in common practice.

995	Yes	Yes	Official	Post Office Protocol 3 over TLS/SSL (POP3S)

1010	Yes	Unofficial	ThinLinc web-based administration interface

1011–1020	Reserved	Reserved	Official

1023	Reserved	Reserved	Official

Yes	Yes	Unofficial	z/OS Network File System (NFS) (potentially ports 991–1023)

Sentence(s)

A TCP connection is on the "well-known port" for SMTP: port 25.

final_sentence: A TCP connection is on the "well-known port" for SMTP: port 25.