Well-known Ports

Port 21 is the FTP control port.

Port 22 is the standard port for SSH (Secure Shell), SFTP (SSH File Transfer Protocol), and SCP (Secure Copy).

Port 25 is the original SMTP port for server-to-server email delivery.

Port 53 is the DNS port.

Port 80 is the default port for HTTP (unencrypted web traffic).

Port 443 is the default port for HTTPS, HTTP/2, and HTTP/3 (over QUIC/UDP).

Port 587 is the standard port for authenticated email submission using STARTTLS.

Port 3306 is the default MySQL and MariaDB database port.

Port 5432 is the default PostgreSQL database port.

Port 6379 is the default Redis port.

Port 8080 is the most common alternative HTTP port used for development servers, proxies, and services that can't bind to port 80 (which requires root on Linux).

Port 27017 is the default MongoDB port.

Port 110 is the POP3 port for downloading email from a mail server.

Port 143 is the IMAP port for accessing email.

Port 465 is SMTPS – SMTP with implicit TLS (TLS established immediately on connect, before any SMTP commands).

Port 993 is IMAPS – IMAP with implicit TLS.

Port 995 is POP3S – POP3 with implicit TLS.

Port 1433 is the default Microsoft SQL Server port.

Port 5672 is the default AMQP 0-9-1 port used by RabbitMQ and other message brokers.

Port 9200 is the Elasticsearch REST API port.

Port 8443 is the standard alternate HTTPS port – used when port 443 is unavailable or reserved.

Port 2181 is the Apache ZooKeeper client connection port.

Port 4222 is the default NATS server client connection port.

Port 5601 is the default Kibana web interface port.

Port 8888 is the default Jupyter Notebook and JupyterLab port.

Port 9092 is the default Apache Kafka broker port for plaintext client connections.

Port 9300 is the Elasticsearch inter-node transport port – used for cluster communication between Elasticsearch nodes, master election, shard replication, and cross-cluster search.

Port 11211 is the default Memcached port (both TCP and UDP).

Port 2375 is the Docker daemon's unencrypted REST API port.

Port 2376 is the Docker daemon's TLS-protected REST API port.

Port 2379 is the etcd client API port – the distributed key-value store used as Kubernetes' backing datastore.

Port 3000 is the most common development server port used by Node.

Port 5000 is Flask's default development server port and a common alternative dev port to 3000.

Port 8500 is the HashiCorp Consul HTTP API and web UI port.

Port 9090 is the Prometheus time-series metrics server port.

Port 9093 is the Prometheus Alertmanager HTTP API and web UI port.

Port 8081 is a common secondary HTTP development port and the default for Confluent Schema Registry and Kafka REST Proxy.

Port 4369 is the Erlang Port Mapper Daemon (EPMD) – a name service for Erlang and Elixir nodes.

Port 5044 is the default Logstash port for the Beats input plugin.

Port 15672 is the RabbitMQ Management Plugin web UI and HTTP API.

Port 16686 is the Jaeger distributed tracing UI port.

Port 4317 is the OpenTelemetry Protocol (OTLP) gRPC port.

Port 9229 is the Node.

Port 10250 is the Kubernetes kubelet's main HTTPS API port.

Port 6443 is the default Kubernetes API server HTTPS port.

Port 2049 is the NFS (Network File System) port for mounting remote filesystems over a network.

Port 111 is the ONC RPC portmapper (rpcbind).

Port 8161 is the Apache ActiveMQ web console port.

Port 9160 is the Apache Cassandra legacy Thrift API port.

Port 7000 is Apache Cassandra's inter-node communication port for cluster gossip and data replication.

Port 8200 is the default HashiCorp Vault HTTP API port.

Port 139 is the NetBIOS Session Service port used by SMBv1 for Windows file and printer sharing over NetBIOS.

Port 161 is the SNMP agent port where managed devices (routers, switches, servers) listen for queries.

Port 162 is the SNMP trap receiver port where management stations listen for unsolicited notifications from devices.

Port 179 is the BGP (Border Gateway Protocol) port used by routers to exchange routing information between autonomous systems.

Port 389 is the LDAP port for directory lookups – user authentication, group membership, and address book queries.

Port 427 is the SLP (Service Location Protocol) port for automatic service discovery on local networks.

Port 445 is the SMB (Server Message Block) port for Windows file sharing, printer access, and named pipes.

Port 464 is the Kerberos password change (kpasswd) port used by Active Directory and MIT Kerberos for password resets.

Port 514 is the traditional Syslog port where network devices send log messages over UDP.

Port 515 is the LPD (Line Printer Daemon) port for Unix print spooling.

Port 543 is the Kerberos-authenticated remote login (klogin) port – a Kerberos-secured version of rlogin.

Port 544 is the Kerberos-authenticated remote shell (kshell/krcmd) port – a secure version of rsh that uses Kerberos tickets for authentication.

Port 548 is the AFP (Apple Filing Protocol) port for macOS file sharing.

Port 554 is the RTSP (Real Time Streaming Protocol) port for controlling media streams from IP cameras, media servers, and surveillance systems.

Port 631 is the IPP (Internet Printing Protocol) port used by CUPS on Linux/macOS for print management.

Port 636 is the LDAPS port – LDAP encrypted with TLS from the start of the connection (implicit TLS).

Port 749 is the Kerberos administration (kadmind) port for managing principals, policies, and keytabs.

Port 873 is the rsync daemon port for efficient file synchronization using delta encoding.

Port 902 is the VMware ESXi host client and console port used by vSphere Client for VM console access (VMRC) and NFC data transfers.

Port 989 is the implicit FTPS data channel port – FTP file transfers encrypted with TLS from connection start.

Port 990 is the implicit FTPS control channel port – FTP commands encrypted with TLS from the first byte.

Port 992 is the TLS-encrypted Telnet port.

Port 1080 is the SOCKS proxy port.

Port 1194 is the default OpenVPN port.

Port 1521 is the Oracle Database TNS (Transparent Network Substrate) listener port.

Port 1723 is the PPTP (Point-to-Point Tunneling Protocol) control channel port.

Port 1812 is the RADIUS authentication port where network access servers (NAS) send authentication requests.

Port 1883 is the MQTT broker port for lightweight publish-subscribe messaging.

Port 2082 is the cPanel web hosting control panel HTTP port.

Port 2083 is the cPanel HTTPS port – the encrypted version of the web hosting control panel.

Port 2087 is the WHM (Web Host Manager) HTTPS port for server-level administration of cPanel servers.

Port 2222 is a common alternate SSH port used to reduce automated brute-force attacks against port 22.

Port 3128 is the default Squid HTTP proxy port.

Port 3268 is the Active Directory Global Catalog LDAP port.

Port 3269 is the TLS-encrypted Active Directory Global Catalog port – the secure equivalent of port 3268.

Port 3389 is the RDP (Remote Desktop Protocol) port for Windows remote desktop access.

Port 3690 is the Subversion (SVN) native protocol port served by svnserve.

Port 4443 is a common alternate HTTPS port used when port 443 is occupied by another service.

Port 4567 is the default port for Ruby Sinatra web framework and several development tools.

Port 4848 is the GlassFish (Payara) application server administration console port.

Port 5060 is the SIP (Session Initiation Protocol) port for VoIP call signaling.

Port 5222 is the XMPP (Jabber) client-to-server port for instant messaging, presence, and real-time communication.

Port 5269 is the XMPP server-to-server (S2S) federation port.

Port 5353 is the mDNS (Multicast DNS) port for zero-configuration name resolution on local networks.

Port 5355 is the LLMNR (Link-Local Multicast Name Resolution) port used by Windows for local name resolution when DNS fails.

Port 5671 is the AMQP (Advanced Message Queuing Protocol) TLS port – the encrypted equivalent of port 5672.

Port 5900 is the VNC (Virtual Network Computing) remote desktop port.

Port 5984 is the CouchDB HTTP API port.

Port 6000 is the X11 (X Window System) display server port.

Port 6660 is an alternate IRC (Internet Relay Chat) port.

Port 6667 is the standard IRC (Internet Relay Chat) default port.

Port 6697 is the standard IRC over TLS port – encrypted IRC connections from the first byte.

Port 7001 is the Oracle WebLogic Server default HTTPS/T3S administration port.

Port 7002 is the default Oracle WebLogic managed server SSL port.

Port 7070 is used by Openfire XMPP server for HTTP binding (BOSH) and historically by RealNetworks RealServer for streaming.

Port 7199 is the Apache Cassandra JMX (Java Management Extensions) monitoring port.

Port 7443 is the Openfire XMPP server TLS-encrypted HTTP binding (BOSH) port.

Port 7474 is the Neo4j graph database HTTP API and Browser interface port.

Port 7687 is the Neo4j Bolt protocol port – a binary protocol optimized for Cypher query execution.

Port 8000 is the most common HTTP development server port.

Port 8008 is an IANA-registered HTTP alternate port used when 80 and 8080 are occupied.

Port 8009 is the AJP (Apache JServ Protocol) connector port for Apache Tomcat.

Port 8042 is the Hadoop YARN NodeManager web UI port showing container status, resource usage, and application logs on each cluster node.

Port 8083 is the default port for Verdaccio (private npm registry) and various HTTP proxy services.

Port 8084 is used by various development web servers and admin interfaces when lower ports are occupied.

Port 8085 was the legacy InfluxDB HTTP API port in older versions.

Port 8086 is the InfluxDB HTTP API port for time-series data ingestion and queries.

Port 8088 is the Hadoop YARN ResourceManager web UI port providing cluster-wide job management, queue monitoring, and application status.

Port 8089 is the Splunk management port used for REST API access, forwarder-to-indexer communication, and deployment server operations.

Port 8123 is the ClickHouse column-oriented database HTTP interface for queries and data ingestion.

Port 8180 is used by JBoss/WildFly application server instances when port 8080 is occupied (port offset configuration).

Port 8243 is the WSO2 API Manager and Enterprise Service Bus HTTPS transport port for API gateway traffic.

Port 8280 is the WSO2 API Manager and Enterprise Service Bus HTTP transport port – the unencrypted equivalent of port 8243.

Port 8291 is the MikroTik Winbox management protocol port.

Port 8333 is the Bitcoin mainnet peer-to-peer port.

Port 8384 is the Syncthing web GUI port for managing file synchronization between devices.

Port 8388 is the default Shadowsocks proxy port.

Port 8444 is the Chia blockchain full node P2P port.

Port 8530 is the WSUS (Windows Server Update Services) HTTP port for distributing Windows updates within an organization.

Port 8649 is the Ganglia monitoring daemon (gmond) port for collecting and sharing host metrics in clusters.

Port 8834 is the Nessus vulnerability scanner web interface and API port.

Port 8880 is used for cPanel webmail (HTTP redirect to HTTPS), Plesk alternate web, and various application servers as an alternate HTTP port.

Port 8883 is the MQTT over TLS (MQTTS) port – the encrypted equivalent of port 1883.

Port 9000 is shared by PHP-FPM (FastCGI process manager), SonarQube code quality platform, Portainer Docker management, and ClickHouse native protocol.

Port 9001 is used by Supervisord (process manager XML-RPC), MinIO console (S3-compatible storage web UI), and ETH2 beacon nodes.

Port 9042 is the Apache Cassandra CQL (Cassandra Query Language) native protocol port.

Port 9043 is the IBM WebSphere Application Server admin console HTTPS port.

Port 9060 is the IBM WebSphere Application Server admin console HTTP (unencrypted) port.

Port 9080 is the IBM WebSphere Application Server default HTTP port for deployed applications.

Port 9091 is shared by Transmission BitTorrent web UI and Prometheus Pushgateway.

Port 9100 is shared by Prometheus Node Exporter (Linux system metrics) and HP JetDirect (network printing raw protocol).

Port 9418 is the Git native protocol (git://) port for read-only anonymous repository access.

Port 9443 is the IBM WebSphere application HTTPS port and WSO2 Carbon management console port.

Port 9500 is the ISPConfig server management panel port.

Port 9600 is the Logstash monitoring API port providing pipeline statistics, JVM metrics, and hot threads.

Port 9800 is used by various WebDAV implementations, development servers, and application-specific services.

Port 9990 is the WildFly (formerly JBoss AS) management console and CLI port.

Port 9997 is the default Splunk receiving port where indexers accept data from Universal and Heavy Forwarders.

Port 9999 is commonly used as a generic development, debug, or testing port.