Network Port Reference

PortProtoService
20TCPFTP data
21TCPFTP control
22TCPSSH / SFTP / SCP
23TCPTelnet
25TCPSMTP
53TCP/UDPDNS
67UDPDHCP server
68UDPDHCP client
69UDPTFTP
80TCPHTTP
88TCP/UDPKerberos
110TCPPOP3
123UDPNTP
135TCPMS RPC
137UDPNetBIOS name
139TCPNetBIOS session
143TCPIMAP
161UDPSNMP
162UDPSNMP trap
179TCPBGP
389TCP/UDPLDAP
443TCPHTTPS
445TCPSMB
465TCPSMTPS
500UDPIKE
514UDPSyslog
587TCPSMTP submission
636TCPLDAPS
853TCP/UDPDNS over TLS
873TCPrsync
993TCPIMAPS
995TCPPOP3S
1080TCPSOCKS
1194UDPOpenVPN
1433TCPSQL Server
1521TCPOracle DB
1883TCPMQTT
2049TCP/UDPNFS
2181TCPZooKeeper
2375TCPDocker API
2379TCPetcd client
3000TCPDev servers / Grafana
3128TCPSquid proxy
3306TCPMySQL / MariaDB
3389TCPRDP
3478UDPSTUN / TURN
4369TCPEPMD
4500UDPIPsec NAT-T
5044TCPBeats / Logstash
5060TCP/UDPSIP
5222TCPXMPP
5432TCPPostgreSQL
5671TCPAMQP over TLS
5672TCPAMQP
5900TCPVNC
5984TCPCouchDB
6379TCPRedis
6443TCPKubernetes API
6514TCPSyslog over TLS
7000TCPCassandra inter-node
8000TCPDev HTTP
8080TCPHTTP alternate
8443TCPHTTPS alternate
8500TCPConsul
8600TCP/UDPConsul DNS
8883TCPMQTT over TLS
9000TCPMinIO / SonarQube / PHP-FPM
9042TCPCassandra CQL
9090TCPPrometheus
9092TCPKafka
9093TCPAlertmanager
9100TCPnode_exporter
9200TCPElasticsearch / OpenSearch
9418TCPGit
10250TCPkubelet API
11211TCP/UDPMemcached
15672TCPRabbitMQ management
27017TCPMongoDB

The ports engineers actually meet, searchable by number, service or protocol.

Port FAQs

What are well-known, registered and ephemeral ports?

Ports 0 to 1023 are well-known and historically require privileges to bind; 1024 to 49151 are registered for applications; 49152 to 65535 are ephemeral, used by clients as the source port of outgoing connections. Linux commonly uses 32768 to 60999 for ephemeral ports.

Why do some services use TCP and others UDP?

TCP gives ordered, reliable delivery at the cost of connection setup, suiting databases, web and mail. UDP is fire-and-forget, suiting DNS queries, clock sync, VoIP media and games, where a late answer is worthless anyway. Some protocols use both, and HTTP/3 moved the web onto UDP via QUIC.

Which ports should never be exposed to the internet?

Unauthenticated data and management planes: databases such as 3306, 5432, 6379, 27017 and 9200, SMB on 445, RDP on 3389 without a gateway, the Docker API on 2375, and the kubelet on 10250. These are scanned constantly; reach them over VPNs or private networks instead.

Can a service run on a different port than listed?

Yes, these are defaults and conventions, not rules. Anything can listen anywhere, which is why firewalls that identify traffic by port alone are only a first approximation.

Does this page look anything up remotely?

No. The table ships with the page, search runs in your browser, and it works offline.