Around 50 ports developers and sysadmins meet every day Protocol (TCP, UDP or both) and a plain explanation of each service Marks which ports are IANA-assigned and which are just conventions Instant search by number, service or keyword, plus category filters Covers web, SSH and VPN, email, databases, message brokers and dev servers

Common Ports

Search by port number, service or keyword, or filter by category.

What is a network port?

An IP address identifies a machine, and a port number (0 to 65535) identifies a service on that machine, so one server can run a web server on port 443 and SSH on port 22 at the same time. Ports 0 to 1023 are "well-known" and normally need administrator rights to bind, 1024 to 49151 are registered ports, and 49152 and above are dynamic ports used for outgoing connections. IANA keeps the official registry, but many popular tools such as dev servers, Redis or Kafka use ports by convention. Knowing them is essential for configuring firewalls, cloud security groups, Docker port mappings and for reading netstat or ss output.

Features

• Around 50 ports developers and sysadmins meet every day
• Protocol (TCP, UDP or both) and a plain explanation of each service
• Marks which ports are IANA-assigned and which are just conventions
• Instant search by number, service or keyword, plus category filters
• Covers web, SSH and VPN, email, databases, message brokers and dev servers

Simple reference

The table is part of the page and the search runs in your browser. Nothing is scanned: this is a reference, not a port scanner.

Reference only, no scanning.

How to use the Common Ports

1
Type a port number such as 5432, a service name such as "redis" or a word such as "vpn" in the search box.
2
Use the category chips to list, for example, all database ports before writing firewall rules.
3
Check the protocol column: DNS, NTP, DHCP and WireGuard need UDP rules, not only TCP.
4
Look at the badge: IANA ports are official assignments, Convention ports are popular defaults that you can and often should change.

Practical examples

Opening a cloud firewall

For a typical web server, allow 443 (and 80 for redirects) from anywhere, 22 only from your office IP, and keep database ports such as 3306 or 5432 closed to the internet.

Docker port mappings

docker run -p 8080:80 nginx publishes the container port 80 on host port 8080. Use the list to pick host ports that do not clash with services already running.

Reading netstat or ss

When ss -tlnp shows something listening on 6379 or 27017, you know a Redis or MongoDB instance is running and should check it is not exposed publicly.

Email client setup

Use 587 with STARTTLS or 465 with implicit TLS to send mail, 993 for IMAP over TLS and 995 for POP3 over TLS. Port 25 is for server-to-server delivery and is often blocked for home users.

Frequently asked questions

What is the difference between TCP and UDP ports?+

They are separate number spaces: TCP port 53 and UDP port 53 are different sockets. TCP is connection-oriented and reliable, UDP is faster with no handshake, which suits DNS queries, VoIP, games and VPNs.

Which ports should never be open to the internet?+

Databases (3306, 5432, 6379, 27017, 9200), Docker API (2375), SMB (445), RDP (3389) and Telnet (23) are common targets. Keep them on a private network or behind a VPN.

Does changing the SSH port improve security?+

It cuts noise from automated scans but is not real protection. Use key-based authentication, disable password login and consider allow-listing IPs or fail2ban.

Why do dev servers use 3000, 5173 or 8000?+

They are above 1024, so no admin rights are needed, and each framework picked its own default. Any free port works, change it if two projects clash.

Port	Protocol	Service	What it is used for
20-21	TCP	FTPIANA File Transfer Protocol: 21 for commands, 20 for data in active mode. Unencrypted; prefer SFTP or FTPS.	File Transfer Protocol: 21 for commands, 20 for data in active mode. Unencrypted; prefer SFTP or FTPS.
22	TCP	SSH / SFTP / SCPIANA Secure Shell for encrypted remote login, plus SFTP/SCP file transfer and Git over SSH.	Secure Shell for encrypted remote login, plus SFTP/SCP file transfer and Git over SSH.
23	TCP	TelnetIANA Old unencrypted remote terminal. Still found on network gear; never expose it to the internet.	Old unencrypted remote terminal. Still found on network gear; never expose it to the internet.
25	TCP	SMTPIANA Mail delivery between servers. Often blocked for home connections to stop spam.	Mail delivery between servers. Often blocked for home connections to stop spam.
53	TCP/UDP	DNSIANA Domain Name System lookups. UDP for normal queries, TCP for large answers and zone transfers.	Domain Name System lookups. UDP for normal queries, TCP for large answers and zone transfers.
67-68	UDP	DHCPIANA Automatic IP address assignment: 67 on the server, 68 on the client.	Automatic IP address assignment: 67 on the server, 68 on the client.
69	UDP	TFTPIANA Trivial File Transfer Protocol, used for network boot (PXE) and device firmware. No authentication.	Trivial File Transfer Protocol, used for network boot (PXE) and device firmware. No authentication.
80	TCP	HTTPIANA Plain-text web traffic. Today mostly used to redirect visitors to HTTPS.	Plain-text web traffic. Today mostly used to redirect visitors to HTTPS.
110	TCP	POP3IANA Downloads email from a mailbox and usually deletes it from the server. Unencrypted.	Downloads email from a mailbox and usually deletes it from the server. Unencrypted.
123	UDP	NTPIANA Network Time Protocol keeps server and device clocks in sync.	Network Time Protocol keeps server and device clocks in sync.
143	TCP	IMAPIANA Reads email while keeping it on the server, synced across devices. Unencrypted; prefer 993.	Reads email while keeping it on the server, synced across devices. Unencrypted; prefer 993.
161-162	UDP	SNMPIANA Simple Network Management Protocol: 161 for queries, 162 for traps from routers and switches.	Simple Network Management Protocol: 161 for queries, 162 for traps from routers and switches.
389	TCP/UDP	LDAPIANA Directory services such as Active Directory and OpenLDAP for users, groups and logins.	Directory services such as Active Directory and OpenLDAP for users, groups and logins.
443	TCP/UDP	HTTPS (HTTP/3 over UDP)IANA Encrypted web traffic over TLS. UDP 443 carries HTTP/3 (QUIC).	Encrypted web traffic over TLS. UDP 443 carries HTTP/3 (QUIC).
445	TCP	SMBIANA Windows file and printer sharing (SMB/CIFS). A frequent ransomware target; keep it internal.	Windows file and printer sharing (SMB/CIFS). A frequent ransomware target; keep it internal.
465	TCP	SMTPSIANA SMTP submission with implicit TLS, used by mail clients to send email securely.	SMTP submission with implicit TLS, used by mail clients to send email securely.
514	UDP	SyslogIANA Sends system logs to a central log server.	Sends system logs to a central log server.
587	TCP	SMTP SubmissionIANA Mail submission from clients to their provider, usually with STARTTLS and login.	Mail submission from clients to their provider, usually with STARTTLS and login.
636	TCP	LDAPSIANA LDAP over TLS for encrypted directory queries.	LDAP over TLS for encrypted directory queries.
853	TCP	DNS over TLSIANA Encrypted DNS over TLS (DoT) for private name lookups.	Encrypted DNS over TLS (DoT) for private name lookups.
993	TCP	IMAPSIANA IMAP over TLS: the secure way for mail apps to read email.	IMAP over TLS: the secure way for mail apps to read email.
995	TCP	POP3SIANA POP3 over TLS for securely downloading email.	POP3 over TLS for securely downloading email.
1194	UDP	OpenVPNIANA Default port of OpenVPN tunnels (TCP is also possible).	Default port of OpenVPN tunnels (TCP is also possible).
1433	TCP	Microsoft SQL ServerIANA Default port of Microsoft SQL Server.	Default port of Microsoft SQL Server.
1521	TCP	Oracle DatabaseConvention Oracle Database listener (TNS). Oracle's official IANA ports for TLS are 2483/2484.	Oracle Database listener (TNS). Oracle's official IANA ports for TLS are 2483/2484.
1883	TCP	MQTTIANA MQTT message broker for IoT devices; 8883 is the TLS version.	MQTT message broker for IoT devices; 8883 is the TLS version.
2049	TCP/UDP	NFSIANA Network File System for mounting remote directories on Linux and Unix.	Network File System for mounting remote directories on Linux and Unix.
2375-2376	TCP	Docker APIIANA Docker daemon API: 2375 unencrypted, 2376 with TLS. Exposing 2375 gives full control of the host.	Docker daemon API: 2375 unencrypted, 2376 with TLS. Exposing 2375 gives full control of the host.
3000	TCP	Node.js / Next.js / Rails dev serverConvention Common default for Node.js, Next.js, Express and Rails development servers.	Common default for Node.js, Next.js, Express and Rails development servers.
3306	TCP	MySQL / MariaDBIANA Default port of MySQL and MariaDB.	Default port of MySQL and MariaDB.
3389	TCP/UDP	RDPIANA Remote Desktop Protocol for Windows. A favorite brute-force target; put it behind a VPN.	Remote Desktop Protocol for Windows. A favorite brute-force target; put it behind a VPN.
5000	TCP	Flask dev serverConvention Default port of the Flask development server; also used by macOS AirPlay Receiver.	Default port of the Flask development server; also used by macOS AirPlay Receiver.
5173	TCP	Vite dev serverConvention Default port of the Vite development server.	Default port of the Vite development server.
5432	TCP	PostgreSQLIANA Default port of PostgreSQL.	Default port of PostgreSQL.
5672	TCP	AMQP (RabbitMQ)IANA AMQP protocol used by RabbitMQ and other message brokers.	AMQP protocol used by RabbitMQ and other message brokers.
5900	TCP	VNCIANA VNC remote desktop (display :0; display :1 uses 5901).	VNC remote desktop (display :0; display :1 uses 5901).
6379	TCP	RedisConvention Default port of Redis and Valkey. Has no password by default; never expose it publicly.	Default port of Redis and Valkey. Has no password by default; never expose it publicly.
6443	TCP	Kubernetes API serverConvention Kubernetes API server, used by kubectl and cluster components.	Kubernetes API server, used by kubectl and cluster components.
8000	TCP	Django / Python http.serverConvention Default for Django runserver and python -m http.server.	Default for Django runserver and python -m http.server.
8080	TCP	HTTP alternate / proxyIANA Alternative HTTP port for proxies, Tomcat and app servers running without root.	Alternative HTTP port for proxies, Tomcat and app servers running without root.
8443	TCP	HTTPS alternateConvention Common alternative HTTPS port for admin panels and app servers.	Common alternative HTTPS port for admin panels and app servers.
9092	TCP	Apache KafkaConvention Apache Kafka brokers for event streaming.	Apache Kafka brokers for event streaming.
9200	TCP	Elasticsearch / OpenSearchConvention Elasticsearch and OpenSearch REST API (9300 for node-to-node traffic).	Elasticsearch and OpenSearch REST API (9300 for node-to-node traffic).
11211	TCP/UDP	MemcachedIANA Memcached in-memory cache. Disable UDP; open servers were abused for DDoS amplification.	Memcached in-memory cache. Disable UDP; open servers were abused for DDoS amplification.
27017	TCP	MongoDBConvention Default port of MongoDB.	Default port of MongoDB.
51820	UDP	WireGuardConvention Default port of WireGuard VPN tunnels.	Default port of WireGuard VPN tunnels.