popular port numbers list

Common Ports Cheat Sheet: The Ultimate List

Perhaps you’re angsty that you’ve forgotten what a certain port number meant. Rest assured, you don’t have to remember all 65,535 port numbers. With so much information to remember, it’s understandable if you forget a common port. That’s why we put together this cheat sheet of common network ports for you.

A crucial domain of expertise in IT-related certifications such as Cisco Certified Network Associate (CCNA) and those of CompTIA is port numbers and associated services , which this common ports and protocols cheat sheet covers. If you want to remember a port number or protocol, this cheat sheet will help everyone, from students to professionals.

Get a copy of this common ports cheat sheet here to keep on your desk. When you're ready, scroll below to find the port you’re looking for.

Common Ports Cheat Sheet Search

Search our Common Ports cheat sheet to find the right cheat for the term you're looking for. Simply enter the term in the search bar and you'll receive the matching cheats available.

Common Ports and Protocols Cheat Sheet

The following tables cover services (and malware) that use common TCP ports and some UDP or SCTP ports.

Well-known/System Ports: 0 – 1023

Registered Ports: 1024 – 49151

Dynamic/Private Ports: 49152 – 65535

You may use these ports for custom applications free from concerns that it may clash with existing processes.

The Most Common Ports for Exams

If you’re studying for IT certifications such as CCNA , focus on these ports:

We hope that you found this cheat sheet useful. Familiarity with ports and protocols is vital to building secure applications and troubleshooting problems on computer networks. Whether you're studying or working, this cheat sheet of common network ports will help you in academic and professional settings.

For further resources, or if you’re curious about how ports and protocols fit into cyber security, look into network security courses available with our StationX Accelerator Program .

Frequently Asked Questions

FTP: ports 20-21; SSH/SCP: port 22; HTTP: 80; HTTPS: 443; POP3: 110; POP3 over SSL: 995; IMAP: 143; IMAP over SSL: 993. We recommend you download the graphic in Well-known/System Ports .

It depends on whether you’re referring to system ports (1024) or want to include ports registered with apps (49152) because system ports range from 0 through 1023, and registered ports span 1024 – 49151.

FTP: ports 20-21; SSH/SCP: port 22; Telnet: 23; SMTP: 25; DNS: 53; HTTP: 80; POP3: 110; IMAP: 143; HTTPS: 443.

FTP: port 21; SSH/SCP: 22; Telnet: 23; SMTP: 25; DNS: 53; POP3: 110; IMAP: 145; HTTP: 80; HTTPS: 443; MySQL: 3306; RDP: 3389; VNC: 5900.

The following are the three types of ports with corresponding port number ranges: • Well-known/System ports: 0 – 1023 • Registered ports: 1024 – 49151 • Dynamic/Private ports: 49152 – 65535

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Nathan House is the founder and CEO of StationX. He has over 25 years of experience in cyber security, where he has advised some of the largest companies in the world. Nathan is the author of the popular "The Complete Cyber Security Course", which has been taken by over half a million students in 195 countries. He is the winner of the AI "Cyber Security Educator of the Year 2020" award and finalist for Influencer of the year 2022.

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Nathan, thank you for supplying this sheet. It comes in handy when you’re trying to remember what a particular port is used by.

Our pleasure.

Thank you, Nathan

This is a great single point to reference all default ports. Thank you!!!

Very good, it will be in front of me!

Ports on computers are required for networking, and without them, the computer would be completely isolated and it would be unable to communicate with other devices. So thank you for proving this list of the Common TCP and UDP Port numbers.

After resetting my router cause the password got changed and all the setting were changed to gain access to my computer. I spent about 20 minutes setting up the router. It appears the router never got set up from the cable company when it was installed. So if you have not done so lately check your router and settings.

Cool, Thanks for sharing!!

Sorry Nathan, i did not leave a comment for this “Common Ports” Chart last-week. I am glad i signed up to your news letter you are a good researcher. thank you for sharing with us all..

Nathan, I must thank you for these cheat sheets! They’ve been great on my learning and certification journey!

Thank you too!

Really really useful.Thanks a lot!!

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14 common network ports you should know

Opensource.com

The physical ports on your computer allow communicate with peripheral devices such as your keyboard and mouse and to connect with internet devices via Ethernet cables.

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Witin computer networking, ports serve a similar purpose. When a computer system seeks to connect to another computer, the port serves as a communication endpoint. It is also possible for different services running on the same computer to expose various ports and communicate with one another using these ports. In simple terms, if a software application or service needs to communicate with others, it will expose a port. Ports are identified with positive 16-bit unsigned integers, ranging from 0 to 65535. Other services use this port number to communicate with the service or app. Port numbers are divided into three ranges: well-known ports, registered ports, and dynamic or private ports.

Well-known ports (also known as system ports ) are numbered from 0 through 1023. For example, to connect to the host example.com via SSH, I would use this command:

In this example, -v stands for verbose, and you should see output similar to this:

As shown, SSH is trying to connect to example.com using port number 22. You may use the -p option to specify another port number; otherwise, SSH will default to 22.

The Internet Assigned Numbers Authority (IANA) has assigned port numbers to commonly used services like SSH, FTP, HTTP, HTTPS, and others. Here are some of the most common ones:

In my work, I most commonly come across ports 80, 443, 20, 21, 22, 23, 25, and 53. Knowing these ports can help you work more efficiently.

What ports do you use the most, and why?

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Port number is a 16-bit numerical value that ranges from 0 to 65535. Well-known port (0-1023), registered port (1024-49151), and dynamic port is three types of port number space. (49152-65535).

These ports can be opened and used by software applications and operating system services to send and receive data over networks (LAN or WAN) that employ certain protocols (eg TCP, UDP).

For example, we use 80 for HTTP-web-based plain-text surfing and 443 for HTTPS-web-based encrypted websites in our daily work.

To conclude, a port is a logical form to identify system activities or various network services used to create local or network-based communications.

What are the functions of ports?

When interacting over the Internet, TCP and UDP protocols make connections, recompile data packages after the transfer, and then deliver them to applications on the recipient’s device. For this handover to work, the operating system must install and open the gateway for the transfer. Each door has a unique code number. After transmission, the receiving system uses the port number to determine where the data should be sent. The port numbers of the sender and receiver are always included in the data packet.

Ports are assigned sequential numbers from 0 to 65535. Some of these codes are standardized, meaning they are assigned to certain uses. Since code numbers are universally recognized and permanently assigned, these standard ports are also known as well-known ports. Registered ports are those that organizations or software developers have registered for their applications. Registration is handled by the Internet Assigned Numbers Authority (IANA). A diverse selection of dynamically assigned port numbers is also available. For example, when viewing websites, browsers use these ports. After that, the port number is free again.

Why is it important to know these ports?

Any security researcher, bug bounty hunter, or anyone working with service configuration would benefit from this. Knowing how to do more thorough scans such as version detection or known vulnerabilities for ancient services that are still operating in the infrastructure, especially when using tools like Nmap, is handy when getting to know these protocols and services. 

The most 50 significant ports are listed here:

The following are some of the most common service names, transport protocol names, and port numbers used to differentiate between specific services that employ TCP, UDP, DCCP, and SCTP.

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Common Ports Cheat Sheet

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It’s a pain trying to memorize port numbers and their corresponding service names and protocols. So, we created this concise cheat sheet of common network ports and their associated protocols and service names for you to use as a quick reference.

Feel free to print it out and hang it up or share a link to it with your colleagues and peers. Use it to speed up port identification or as a training resource for onboarding new network administrators or engineers.

Free Common Port Cheat Sheet

Click on the network port chart above to view the printable, searchable PDF version. Scroll down below for the port list tables.

This list is by no means exhaustive. It just lists the most frequently used ports. There are a total of 65,535 TCP/UDP ports. They are divided into 3 classes:

• Well Known Ports (1-1023) – Reserved ports registered with IANA for specific services.
• Registered Ports (1024-49151) – Also registered with IANA but not as commonly used.
• Dynamic/Private Ports (49152-65535) – Reserved by IANA for proprietary services or private use.

IANA (Internet Assigned Numbers Authority), in case you’re wondering, is the organization that oversees global IP address allocation and port classification.

Some common protocols that use these ports:

• TCP (Transmission Control Protocol)
• UDP (User Datagram Protocol) – Only one port needed for bidirectional traffic
• SCTP (Stream Control Transmission Protocol)
• DCCP (Datagram Congestion Control Protocol)

Common Well-known/System Ports in Computer Networking

Well-known network ports range from 0 to 1023. These ports are assigned by IANA and listed in RFC 1700 . On most systems they can only be used by system (or root) processes or by programs executed by privileged users. Some well-known ports use TCP, some use UDP, and some can be configured to use either. 

Well-known TCP ports are used by applications that rely on TCP as the transport protocol. Examples:

• FTP (File Transport Protocol) uses TCP ports 20 and 21
• Telnet uses TCP port 23

Well-known UDP ports are used by applications relying on UDP. Examples:

• TFTP (Trivial File Transport Protocol) uses UDP port 69
• SNMP uses UDP port 161 for messages and UDP port 162 for traps

Knowledge of these ports is helpful for network engineers looking for work as they are popular topics asked about in technical interviews.

Common Registered Network Ports

Registered network ports are ports in the range of 1024 to 49151 that have been officially registered with the Internet Assigned Numbers Authority (IANA) for specific services and applications.

Some key points about registered ports:

• They come after well-known ports (0-1023) and before dynamic/private ports (49152-65535).
• Anyone can register a port in this range with IANA for their application/service.
• Registration ensures the port number is standardized and should not be used by other services.
• Examples include port 3306 for MySQL, port 1521 for Oracle database, port 1723 for PPTP.
• Not as commonly used as well-known ports, but still important for avoiding conflicts.
• Provide an official way to allocate ports for proprietary applications and organizational services.
• The full list of registered ports is maintained by IANA and published on their website.
• Helpful for network administration to know what traffic these registered ports are associated with.

Common Dynamic/Private Network Ports

Dynamic/Private network ports refer to the range of ports from 49152 to 65535 that are not officially registered with IANA for any specific service or application and are available for private or temporary use. 

They can be used by applications dynamically as needed, usually for establishing temporary connections. Often they are used by client-side applications that initiate connections to servers on well-known or registered ports. 

A common example of dynamic network port use is Ephemeral Ports. These are short-lived transport layer ports used when an application on a client device makes an outgoing connection to a server. They allow a client application to use a random available port for its side of the connection which has multiple benefits from enabling multiple connections from the same client application to traversing firewalls as most firewalls are configured by default to allow connections from ephemeral ports to well-known ports.

The dynamic/private port range also provides ports for private or customized services within an organization since they are unregistered.

Top 35 Most Common Ports for Certification Exams and Interviews

Prepping for an exam or interviewing for a role in networking or a networking adjacent field? Prioritize memorizing the ports below.

In my experience, these are the ports most frequently used in certification exams and to quiz candidates in technical interviews.

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About TCP/UDP Ports

• Port 0 to 1023: These TCP/UDP port numbers are considered as well-known ports. These ports are assigned to specific server sevice by the Internet Assigned Numbers Authority (IANA). For example, port 80 is used by web servers.
• Port 1024 to 49151: These are ports that an organization, such as application developers, can register with IAMA to be used for a particular service. These should be treated as semi-reserved.
• Port 49152 to 65535: These are port numbers used by client programs, such as a web browser. When you visit a web site, your web browser will assign that session a port number from within this range. As an application developer, you are free to use any of these ports.
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Tcp and udp port numbers – complete list.

This is a list of Internet socket port numbers used by application communication with TCP and UDP on the Transport Layer of the Internet Protocol Suite for the host-to-host communications.

Let’s see who makes it possible? The Internet Assigned Numbers Authority (IANA) assigns all port numbers except Dynamic or Private ports. IANA is a standards organization in the world that is responsible for assigning various addressing standards.

There are different types of port numbers: Well Known Ports (Numbers 0 to 1023), Registered Ports (Numbers 1024 to 49151) and Dynamic or Private Ports (Numbers 49152 to 65535). The last porn number type  Dynamic or Private Ports  will not appear on our list because they are cannot be registered with IANA. This range is used for custom or temporary purposes and for automatic allocation of ephemeral ports. They are usually assigned dynamically to client applications when initiating a connection. It is not very common for a client to connect to a service using a Dynamic or Private Port, sometimes some peer-to-peer file sharing programs do.

We will introduce the list of the ports with short description of different port types.

Using both TCP and UDP is also normal sometime. Some applications may use both TCP and UDP. For example, the low overhead of UDP with his short header enables DNS to serve many client requests very quickly. However, sending the requested information sometimes may require the reliability of TCP. In that case, the port number of 53 that is a well known port number is used by both protocols with this service.

Let’s see the list of port numbers:

• Well-known ports
• Registered Ports

Well Known Ports (Numbers 0 to 1023) – These numbers are reserved for services and applications. They are commonly used for applications such as HTTP (web server) POP3/SMTP (e-mail server) and Telnet. By defining these well-known ports for server applications, client applications can be programmed to request a connection to that specific port and its associated service.

Registered Ports >> Registered Ports

Registered Ports (Numbers 1024 to 49151) – These port numbers are assigned to user processes or applications. These processes are primarily individual applications that a user has chosen to install rather than common applications that would receive a Well Known Port. When not used for a server resource, these ports may also be used dynamically selected by a client as its source port.

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This is very helpful. Thank you for the information! You may want to change a word in the sentence (The last porn number type Dynamic or Private Ports.).

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50 Common Ports You Should Know

Introduction.

In the world of computer networking, ports play a crucial role in facilitating communication between different devices. A port can be defined as a logical channel through which information streams between two devices. Each port has a unique number assigned to it, known as a port number. Understanding port numbers and their comparing administrations is fundamental for anybody who works with computer systems.

In this article, we'll examine 50 of the most common ports that you should know. These ports are assembled into different types based on their characteristics and utilization. We'll investigate their highlights, significance, and centrality in computer organizing.

Discuss About 50 Common Ports You Should Know?

These ports are used to facilitate communication between devices on the network and are essential for network administrators and IT professionals to understand.

Every port in computer networking is associated with a specific protocol or service, and each protocol or service is assigned a standard port number by the Internet Assigned Numbers Authority (IANA). These would be organized into three ranges - well-known ports (0 to 1023), registered ports (1024 to 49151), and dynamic/private ports (49152 to 65535).

The article gives a comprehensive list of the 50 most commonly utilized ports, their related conventions, and the sorts of administrations that ordinarily utilize them. It too incorporates a brief clarification of how to utilize harbor filtering instruments to identify open ports and vulnerabilities.

Well-Known Ports

Well-known ports are those ports whose numbers range from 0 to 1023. They are assigned to specific services and protocols, and their numbers are standardized by the Internet Assigned Numbers Authority (IANA). Some common well-known ports include −

Port 80: HTTP (HyperText Transfer Protocol)

Port 21: FTP (File Transfer Protocol)

Port 25: SMTP (Simple Mail Transfer Protocol)

Port 22: SSH (Secure Shell)

Port 443: HTTPS (HyperText Transfer Protocol Secure)

Port 53: DNS (Domain Name System)

Registered Ports

Registered ports are those ports whose numbers range from 1024 to 49151. They are assigned to user processes or applications by the IANA upon request. Some commonly registered ports include −

Port 3306: MySQL Database

Port 5432: PostgreSQL Database

Port 3389: Remote Desktop Protocol (RDP)

Port 27017: MongoDB Database

Port 1521: Oracle Database

Dynamic or Private Ports

These ports whose numbers range from 49152 to 65535. They are used by client applications to initiate communication with servers. Some common dynamic or private ports include −

Port 49152: Windows RPC (Remote Procedure Call)

Port 5353: mDNS (Multicast Domain Name System)

Port 5672: AMQP (Advanced Message Queuing Protocol)

Port 5355: LLMNR (Link-Local Multicast Name Resolution)

Port 49153: Windows RPC (Remote Procedure Call)

Impact of ports on Computer Networks

Port numbers play a vital role in the security of computer networks.

Misconfigured ports can lead to security breaches and data leaks.

Understanding port numbers and their corresponding services can help in the identification and prevention of cyber-attacks.

Significance of ports

Ports are the backbone of computer organizing and empowering communication between different devices and applications.

Ports encourage the exchange of information between different protocols and administrations.

The standardization of well-known ports by the IANA guarantees that different devices can communicate with each other consistently.

Some other common ports are

Telnet (23) - Telnet protocol to ensure effective communication along with the remote server.

POP3 (110) - Post Office Protocol version 3 for email retrieval.

IMAP (143) - Internet Message Access Protocol for email retrieval.

DHCP (67/68) - Dynamic Host Configuration Protocol for IP address allocation.

NTP (123) - Network Time Protocol for time synchronization.

SNMP (161/162) - Simple Network Management Protocol to verify the functionality of the network and management of network.

SMB (445) - Server Message Block protocol for file sharing and printer sharing.

AFP (548) - Apple Filing Protocol for file sharing between Macs.

NetBIOS (137-139) - NetBIOS protocol for network communication between Windows devices.

HTTP Proxy (8080) - HTTP proxy server.

SOCKS (1080) - SOCKS proxy server.

MySQL (3306) - MySQL database server.

MSSQL (1433) - Microsoft SQL Server database server.

Oracle (1521) - Oracle database server.

LDAP (389/636) - Lightweight Directory Access Protocol for directory services.

SMB2 (5722) - SMB version 2 protocol.

IKE (500) - Internet Key Exchange protocol for VPN connections.

L2TP (1701) - Layer 2 Tunneling Protocol for VPN connections.

PPTP (1723) - Point-to-Point Tunneling Protocol for VPN connections.

SIP (5060/5061) - Session Initiation Protocol for VoIP communication.

RTP (16384-32767) - Real-time Transport Protocol for audio and video transmission.

RTCP (16384-32767) - Real-time Control Protocol for audio and video transmission.

HTTPS Proxy (3128) - HTTPS proxy server.

Squid (3128) - Squid proxy server.

VNC (5900) - Virtual Network Computing for remote access.

IRC (6667/6697) - Internet Relay Chat for real-time communication.

Bonjour (5353) - Bonjour protocol for network discovery and communication.

NFS (2049) - Network File System for file sharing.

Redis (6379) - Redis key-value store.

Memcached (11211) - Memcached distributed memory caching system.

Rsync (873) - Remote synchronization for file transfers.

Zeroconf (5353) - Zero Configuration Networking for automatic network configuration.

XMPP (5222/5223) - Extensible Messaging and Presence Protocol for instant messaging.

VMware vSphere Client (443) - VMware vSphere Client for virtualization.

In conclusion, understanding the common ports used in computer networking is essential for IT professionals and network administrators. Being aware of these ports can help them troubleshoot network issues and ensure smooth communication between devices on the network.

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Port Numbers Used for Computer Networks

TCP and UDP ports explained

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What Is a Port Number in Networking?

How port numbers work, when you may need to take action with port numbers, open and closed ports.

In computer networking , port numbers are part of the addressing information used to identify the senders and receivers of messages. They are associated with TCP/IP network connections and might be described as an add-on to the IP address .

Port numbers allow different applications on the same computer to share network resources simultaneously. Home network routers and computer software work with these ports and sometimes support configuring port number settings.

Networking ports are software-based and unrelated to physical ports that network devices have for plugging in cables.

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Port numbers relate to network addressing . In TCP/IP networking, both TCP and UDP use a set of ports that work together with IP addresses.

These port numbers work like telephone extensions. Just as a business telephone switchboard can use the main phone number and assign each employee an extension number, a computer can have a main address and a set of port numbers to handle incoming and outgoing connections.

In the same way that all employees within a building can use one phone number, one IP address can be used to communicate with various applications behind one router. The IP address identifies the destination computer, and the port number identifies the specific destination application.

This is true whether it's a mail application, file transfer program, or web browser. When you request a website from a web browser, the browser communicates over port 80 for HTTP . Then, the data is sent back over the same port and displays in the program that supports that port (the web browser).

In both TCP and UDP, port numbers start at 0 and go up to 65535. The lower ranges are dedicated to common internet protocols such as port 25 for SMTP and port 21 for FTP.

To find the specific values used by certain applications, view a list of ​ the most popular TCP and UDP port numbers . For Apple software, view the TCP and UDP ports used by Apple software products .

The network hardware and the software automatically process port numbers. Casual users of a network do not see these port numbers and don't need to take any action involving their operation. Individuals can, however, encounter network port numbers in certain situations.

Network administrators may need to set up port forwarding to allow the port numbers of specific applications to pass through a firewall . On home networks, a broadband router supports port forwarding on its configuration screens. A common application of homeport forwarding is for online games that use non-standard ports that the router's built-in firewall blocks.

Network programmers sometimes need to specify port numbers in their code, such as in socket programming.

A website URL will sometimes require a specific TCP port number to be included. For example, http://localhost:8080/ uses TCP port 8080 rather than the default port 80. This is usually seen in software development environments more than in mainstream consumer usage.

Network security enthusiasts also frequently discuss the port number used as a key aspect of attack vulnerabilities and protections. Ports can be classified as either open or closed. Open ports have an associated application that listens for new connection requests, and closed ports do not.

A process called network port scanning detects test messages at each port number to identify which ports are open. Network professionals use port scanning as a tool to measure exposure to attackers and often lock down networks by closing non-essential ports. Hackers, in turn, use port scanners to probe networks for open ports that may be exploitable.

You can use the netstat command in Windows to see information regarding active TCP and UDP connections.

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IP Well Known Port Numbers/ Common TCP

Well Known Port Numbers Information

Below is a list of commonly used well-known protocols and their port number. Additionally, RFC reference will help to have more detail on the enlisted transport-layer common port numbers –

Related- TCP vs UDP

Download the table here.

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ABOUT THE AUTHOR

I am here to share my knowledge and experience in the field of networking with the goal being – “The more you share, the more you learn.”

I am a biotechnologist by qualification and a Network Enthusiast by interest. I developed interest in networking being in the company of a passionate Network Professional, my husband.

I am a strong believer of the fact that “learning is a constant process of discovering yourself.” – Rashmi Bhardwaj (Author/Editor)

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40 Network Protocols with Port Numbers, Transport Protocols and Meanings 

40 Network Protocol Names And Port Numbers With Their Transport Protocols And Meanings tabulated by Precious Ocansey (HND, Network Engineer).

Before going straight to the table.

Firstly, what are Network Protocols?

Network protocols are the languages and rules used during communication in a computer network. There are two major transport protocols namely;

TCP and UDP

TCP   which stands for “Transmission Control Protocol”, is a suite of communication protocols used to interconnect network devices on a local network or a public network like the internet. TCP  is known as “connection-oriented” protocols as it ensures each data packet is delivered as requested. Therefore, TCP is used for transferring most types of data such as webpages and files over the Internet.

UDP which stands for “User Datagram Protocol” is part of the TCP/IP suite of protocols used for data transferring. UDP is a known as a “connectionless-oriented” protocol, meaning it doesn’t acknowledge that the packets being sent have been received. For this reason, the UDP protocol is typically used for streaming media. While you might see skips in video or hear some fuzz in audio clips, UDP transmission prevents the playback from stopping completely.

Furthermore, TCP also includes built-in error checking means TCP has more overhead and is therefore slower than UDP, it ensures accurate delivery of data between systems. Therefore TCP is used for transferring most types of data such as webpages and files over the local network or Internet. UDP is ideal for media streaming which does not require all packets to be delivered.

Port Numbers: They are the unique identifiers given to all protocol numbers so they can be accessed easily.

Below is as written  by Precious Ocansey. The 40 Network Protocols, their port numbers and their transport protocols

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Good job.interesting more grace sir

Iṣẹ rere, diẹ ẹ sii oore ọfẹ

ICMP does not use any port, 1 is its protocol number.

Updated. Thank you

IGMP does not use a transport layer protocol such as TCP or UD

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PortFWD.com - Port Check and IP detection Tool

This page serves as a free utility for remotely verifying if a port is open or closed. It will be useful for users who wish to check to see if a server is running or a firewall or ISP is blocking certain ports.

Your Current Public IP Address is: 81.177.182.154

What is Port Forwarding?

If you have a router at home or your office and you want to access it remotely, you will need to forward ports in order for outside traffic to get into your network. Think of your router as being a huge electric fence or wall, with a few doors or openings. This electric fence, or wall serves as your barrier and security blanket from the scary outside Internet world. Your router comes preconfigured with a few of those doors (or ports) open to let you access the internet, but the others are closed tight. So, in order to run a mail server, game server, access your computer remotely, etc you will need to open an extra door or two in your router in order for the outside traffic to get inside. This is called Port Forwarding

Check out our General Port forwarding Guide for more information.

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