Searchable TCP / UDP port reference
Look up any well-known or commonly used network port. Search by number, service name or keyword, filter by category and protocol, or restrict to the well-known range (0 to 1023). Each entry shows the protocol, the service, a category and a short description, with a badge on legacy cleartext protocols you should avoid exposing. The full dataset and the search run entirely in your browser.
| Port▲ | Proto | Service |
|---|
What this common ports list is for
Every networked service listens on a numbered port so the operating system knows which application should receive an incoming packet. The combination of an IP address and a port is what uniquely identifies a connection endpoint. Knowing which port maps to which service is a daily need for sysadmins, developers, network engineers and anyone reading a firewall rule, a netstat output or a security-scan report. This reference lists the well-known ports from 0 to 1023 together with the most common registered ports above that range, with live search so you can jump straight to the one you need.
Ports are governed by the Internet Assigned Numbers Authority (IANA), which maintains the official registry and splits the 0 to 65535 space into three ranges: well-known, registered and dynamic. The table above is sorted by port number by default; click any column header to re-sort, type in the search box to filter instantly, or use the category and protocol controls to narrow the list to exactly the services you care about.
How port numbers and protocols work together
A port number on its own is ambiguous until you also know the transport protocol. TCP and UDP each have their own independent set of 65536 ports, so TCP 53 and UDP 53 are different endpoints even though DNS uses both. TCP is connection-oriented and reliable, used by HTTP, SSH, SMTP and most application protocols. UDP is connectionless and lightweight, used by DNS queries, DHCP, NTP, VoIP media and modern VPNs such as WireGuard. The Proto column in the table shows which transport each service uses; many services register both.
- Search by number to answer “what runs on port 8080?” – type
8080. - Search by name to answer “which port does PostgreSQL use?” – type
postgres. - Search by keyword to list a whole family – type
database,mailorvpn. - Filter by protocol to see only TCP or only UDP services.
- Well-known only hides everything above 1023 when you want the classic system ports.
Legacy and insecure ports to watch
Several historic protocols transmit credentials or data in cleartext and should never be exposed to an untrusted network. The table flags them with a red badge. The most important to retire or tunnel are Telnet (23), FTP (20/21), the Berkeley r-services rexec/rlogin/rsh (512/513/514), TFTP (69), Finger (79), and SNMP v1/v2c (161). Their modern, encrypted replacements are SSH (22), SFTP or FTPS, SCP, and SNMPv3. Cleartext mail protocols POP3 (110) and IMAP (143) should run only with STARTTLS or be replaced by their TLS variants POP3S (995) and IMAPS (993).
Common ports by category
| Family | Typical ports |
|---|---|
| Web | 80 HTTP, 443 HTTPS, 8080 / 8443 alternates |
25 SMTP, 587 submission, 465 SMTPS, 993 IMAPS, 995 POP3S | |
| Remote access | 22 SSH, 3389 RDP, 5900 VNC, 23 Telnet (legacy) |
| Databases | 3306 MySQL, 5432 PostgreSQL, 1433 MS SQL, 6379 Redis, 27017 MongoDB |
| File transfer | 21 FTP, 22 SFTP, 445 SMB, 2049 NFS, 873 rsync |
| VPN / security | 500/4500 IPsec, 1194 OpenVPN, 51820 WireGuard |
| Infrastructure | 53 DNS, 67/68 DHCP, 123 NTP, 161 SNMP, 389 LDAP |
Privacy and how this tool runs
The entire port dataset is embedded in the page and the search runs in your browser with plain JavaScript. Nothing you type is sent to a server, logged or stored, and there is no autocomplete that calls an external API. You can use the reference offline once the page has loaded.
Frequently asked questions
What are well-known ports?
Well-known ports are the numbers 0 to 1023, assigned by IANA to core internet services such as HTTP (80), HTTPS (443), SSH (22) and DNS (53). On Unix-like systems a process must run as root, or hold the CAP_NET_BIND_SERVICE capability, to bind a listening socket to a port in this range.
What port does SSH / RDP / MySQL use?
SSH listens on TCP 22, Microsoft Remote Desktop (RDP) on TCP 3389, and MySQL or MariaDB on TCP 3306. Type the service name into the search box above to confirm any service instantly, along with its protocol and a short description.
What is the difference between a TCP and a UDP port?
TCP and UDP maintain separate port spaces. TCP is connection-oriented with delivery guarantees and is used by HTTP, SSH and SMTP. UDP is connectionless and fast, used by DNS, DHCP, NTP, VoIP and WireGuard. The same number on TCP and UDP refers to two different endpoints, which is why DNS can use both TCP 53 and UDP 53.
Which ports are dangerous to leave open?
Cleartext legacy protocols are the priority to close or tunnel: Telnet (23), FTP (20/21), the r-services (512-514), TFTP (69) and SNMP v1/v2c (161). Also avoid exposing database ports (3306, 5432, 6379, 27017), SMB (445) and RDP (3389) directly to the internet; put them behind a VPN or SSH tunnel instead.
What is the ephemeral port range?
Ports 49152 to 65535 are the dynamic or ephemeral range. The operating system allocates a port from this range as the source port for each outgoing client connection. You should never configure a server to listen on a fixed ephemeral port because the OS may already be using it for outbound traffic.
Is this the complete IANA port list?
No. The official IANA registry contains thousands of entries, many of them obscure or historical. This reference curates the well-known range plus the registered ports you actually meet in real infrastructure, so the list stays useful rather than overwhelming. For an exhaustive lookup, consult the IANA Service Name and Transport Protocol Port Number Registry.
Related tools and resources
Once you know the port, these tools help you test and secure it.
