List of TCP and UDP port numbers

List of TCP and UDP port numbers

The Transmission Control Protocol (TCP) and the User Datagram Protocol (UDP) are Transport Layer protocols of the Internet Protocol Suite (commonly TCP/IP) for communication between computers. The Internet Assigned Numbers Authority (IANA) is responsible for maintaining the official assignments of port numbers for specific uses.cite web
title= "Port Numbers"
accessdate= 2008-05-25
date= 2008-05-22
format= plain text
publisher= The Internet Assigned Numbers Authority (IANA)


The port numbers are divided into three ranges:
* The "Well Known Ports" are those in the range 0–1023. On Unix-like operating systems, opening a port in this range to receive incoming connections requires administrative privileges or possessing "CAP_NET_BIND_SERVICE" capability [ [ Linux Programmer's Manual—Linux IPv4 protocol implementation] ] .
* The "Registered Ports" are those in the range 1024–49151.
* The "Dynamic and/or Private Ports" are those in the range 49152–65535. Randomly chosen port numbers out of this range are called ephemeral ports. These ports are not permanently assigned to any publicly defined application.

IANA does not enforce this; it is simply a set of recommended uses. Sometimes ports may be used for different applications or protocols than their official IANA designation. This misuse may be, for example, by a Trojan horse, or alternatively by a commonly used program that did not get an IANA registered port or port range.

Table legend

Color coding of table entries
* Official Port/application combination is registered with IANA
* Unofficial Port/application combination is not registered with IANA
* Conflict Port is in use for multiple applications

Well known ports: 1 - 1023

Registered ports: 1024–49151

Only those ports that are commonly used are listed; for full list, refer to the IANA port list.

When investigating TCP traffic, be careful not to confuse the client and server ports. The client port is incremental, typically beginning at 1024 at boot time and wrapping at 4096. If the port you are investigating is in the lower part of this range, it may be a client port. Stateful firewalls identify the server port, but packet sniffers and stateless firewalls do not. For example, a packet sniffer showing a TCP packet with source port 1080 and destination port 1494 might be either the SOCKetS or Citrix Independent Computing Architecture (ICA) protocols. The only way to know for sure is to examine the initial TCP handshake.

With UDP, client port selection depends on the application and may be incremental, fixed to a nonsensical value, or fixed equal to the server port.

Dynamic and/or private ports: 49152–65535

By definition, no ports can be registered in the dynamic range.

ee also

*TCP and UDP port
*Internet Protocol Suite


External links

* [ List of selected/nonstandard TCP/IP ports and related information]
* [ List of TCP/UDP ports with information about trojans and malware]
* [ Windows TCP/IP Ephemeral, Reserved, and Blocked Port Behavior]
* [ Known TCP/UDP ports used by Apple software]

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