Ports how to check open ports

How to Check Which Ports Are Open on a Windows 10 PC

Maybe you’re troubleshooting a network connectivity issue for a specific program, and you need to check whether its port access is open. What if you need to confirm that your NAS device can communicate with your Windows 10 PC? Whatever reason you need to look for open ports, this article provides detailed steps to check them on Windows 10 using several available tools, either built-in or free to download and use.

There are a couple of handy tools to scan open ports in Windows. You’ll see how to do so on NetStat, PortQry.exe, and NirSoft CurrPorts.

Using NetStat to Check for Open Ports in Windows 10

One of the simplest ways to check for open ports is to use NetStat.exe. You can find this tool in the System32 folder on Windows 10. With NetStat, you can see open ports or ports that a specific host uses.

Here’s an explanation of what each letter from the commands means.

Checking for Open Ports with NirSoft CurrPorts

If you find the Command Prompt solution too tricky, a simpler alternative is to use NirSoft CurrPorts. This tool displays your currently opened ports (TCP, IP, and UDP). You’ll also see information about a specific process, such as name, path, version info, etc.

This tool has been around for quite a while and is available for Windows 10. You can find the NirSoft Currports download link at Nirsoft’s website towards the bottom.

Note: Ensure you download the correct version. They have 32-bit and 64-bit versions. The app is portable. Unzip the folder, then run the executable file.

Once you have CurrPorts running, perform the following steps:

Another way is to double-click on a process to see its details in a single window.

Checking for Open Ports Using PortQry.exe

PortQry.exe is another handy tool that lets you scan open ports. You download PortQry (scroll down to see the download) and extract it to run it through the Command Prompt. You can also download PortQryUI (more on that below) as an add-on if you don’t want to use the command line, which is a Graphical User Interface (GUI) for PortQry.

With portqry.exe, you insert specific parameters that you find in the executable’s folder.

How to Run PortQry.exe using Command Prompt

How to Run PortQry.exe using the UI Add-On

For those that prefer to use a graphical interface instead of commands when using PortQry.exe, Microsoft offers an add-on named PortQryUI.

The PortQryUI add-on already includes the necessary version of PortQry, so you don’t need both downloads to use it.

In closing, knowing how to check whether a specific port is open or not can come in handy if you’re troubleshooting a program’s network connection or need a port for a particular game. Luckily, it’s not as challenging to do as it looks.

Out of all the options listed above, Netstat is recommended as it’s built into the OS and usually gives you all the details you need. There might be a few extra steps required compared to CurrPorts, but you don’t have to download anything, and there’s nothing to screw up.

Windows 10 Open Ports FAQs

How do I check if Port 3306 is open in Windows 10?

To verify if port 3306 is open, you can use NetStat, CurrPorts, or PortQry.

To check if port 3306 is open via CurrPorts, just sort by Local Port, then find port 3306. If the port is available, it will show in the list.

To use PortQry.exe to find port 3306, use the Command Prompt. Type -e [3306], then press Enter.

What are Predefined Services in PortQueryUI?

Predefined Services offers details on a small handful of predefined services such as Domains and Trusts, Networking, Exchange Server, etc. The option queries all required ports for the specified services and displays them in the window of the UI.

For those who don’t know where Predefined Services resides, it is directly under the Help tab and in the UI. Both serve different needs.

The Help tab option immediately displays all predefined services without testing any ports. It is a quick reference to each port name, value, and protocol used for each listed service.

The UI option lets you specify what service you want to view and see port statuses.

How To Open Ports In Windows Firewall And Check Open Ports

This is a step-by-step guide about how to Open Ports in Windows Firewall on multiple platforms. Also learn how to check open ports on Windows, Mac, etc:

A firewall is an essential safety precaution for your system and you should never be without it. That’s the reason Windows comes with a standard firewall in place. They protect your network from incoming and outgoing threats by blocking network-enabled ports.

When a program communicates through this port, your firewall checks it with its rules database to see whether it is allowed or not. If it doesn’t know for certain, it asks you for permission to check if a certain program is allowed to access the Internet. This could be very annoying.

Also, sometimes these firewalls might interfere with certain programs. To prevent that from happening, you will need to tell your firewall to allow those programs to communicate with the network. You do this by opening a port in your firewall.

In this article, we will tell you how to open ports in Windows, Mac, and Linux and how to open TCP ports. Also, we will guide you through the process on how to check if ports are open.

What You Will Learn:

How To Open Ports In Windows Firewall

Here we will take you step-by-step on how to open firewall ports on various platforms.

Windows 10 And 7

Sometimes, when you are not connecting properly to the Internet, you might face issues with certain apps and processes on Windows 10.

Firewalls can cause these connectivity issues when it is having trouble in determining whether the incoming and outgoing connections are a threat or not. To avoid this issue, open a port for both incoming and outgoing connections.

Here’s how to open a port in Windows 10.

Opening a Port for Incoming Traffic:

#1) Press Windows Key+S together.

#2) Type Windows Firewall.

#3) Click on Windows Firewall.

#4) Click on Advanced Settings.

#5) Go to Inbound Rules.

#6) Go to the right-hand side pane.

#7) Select New Rule.

#8) Click Port.

#9) Select Next.

#10) Select the Type of Port TCP or UDP.

#11) Go to Specific Local Ports.

#12) Enter a Port Number.

#13) Hit Next.

#14) Select Allow a Connection.

#15) Click on Next.

#16) Select Network Type.

#17) Click Next.

#18) Name your rule.

#19) Click on Finish.

Opening a Port for Outgoing Traffic

Steps for opening a port for outgoing traffic are exactly the same as opening one for the incoming traffic. All you have to do is select Outbound Rules instead of Inbound Rules. Follow the other steps exactly to the mark.

For Mac

Opening ports for Mac is easy, however, when compared to opening one in Windows, it seems a little difficult. macOS firewall, by default, is disabled. That means your machine will accept all incoming and outgoing connections. But if you have turned on the firewall, you might need to open a port to allow a connection in.

This is how you can do it:

#1) Go to the Terminal app.

#3) Now enter sudo nano /etc/pf.conf.

#4) Go to the bottom of all configurations.

#5) Type ‘pass in inet proto tcp from any to any port (add port number) no state. This roughly translates to allowing incoming TCP from any machine to any other machine on that specific port number without inspection.

#6) Hold down Ctrl+X together to exit the nano.

#7) Press Y and hit Enter.

For Linux

There are three ways you can open ports in Linux.

Uncomplicated Firewall for Ubuntu:

#1) Press Ctrl+Alt+T to launch the terminal window.

#2) If Ubuntu Uncomplicated Firewall is running, you will see a status message along with a list of firewall rules and opened ports.

#3) If you see the ‘Status: inactive’ message, type ‘sudo ufw enable’.

#4) Hit Enter.

#5) Type sudo ufw allow (port number) to open a specific port.

#6) If the port service is listed in https://www.fosslinux.com/41271/how-to-configure-the-ubuntu-firewall-ufw.htm/etc/services, instead of the port number, type the name of the service.

#7) To open a specific range of ports, replace the port number in the command with the port start number: the end number/tcp or udp, whichever it is.

#8) For specifying an IP address that can access a port, type sudo ufw allow from (IP address) to any port (port number)

Using ConfigServer Firewall

#1) Log in to your server.

#2) Type ‘cd /etc/csf’.

#3) Hit Enter.

#4) Type ‘vim csf.config’.

#5) Hit Enter.

#6) To add Inbound TCP, go to TCP_IN.

#7) Press i to get into typing mode on vim.

#8) Type the port number you want to open.

#9) For multiple ports, separate each port number with commas.

#10) For outbound TCP, go to TCP_OUT.

#11) Type the port numbers, separated by commas.

#12) Hit ESC.

#13) Type ‘:wq!’.

#14) Press Enter.

#15) Type ‘service csf restart’.

#16) Exit vim.

Using Advanced Policy Firewall

#1) Log in to your server

#2) Type ‘cd /etc/apf’

#3) Type ‘vim conf.apf’

#4) Press Enter

#5) To add inbound ports, go to IG_TCP_CPORTS

#6) Press i to get into typing mode on vim

#7) Type the port numbers, separated by commas

#8) To add outbound ports, go to EG_TCP_CPORTS

#9) Type the port numbers, separated by commas

#10) Hit Esc.

#11) Type ‘:wq!’.

#12) Hit Enter.

#14) Press Enter.

How To Check If Ports Are Open

If you are not sure if a certain port is open, you can always check it as explained below.

In Windows

There are a few ways you can check if ports are open in Windows.

Through Windows Firewall Logs:

#1) Right-click on the start menu.

#2) Select Control Panel.

#3) Go to Administrative Tools.

#4) Click on Windows Firewall with Advanced Settings.

#5) From the right pane, select Properties.

#6) Click on an appropriate firewall profile tab (public/private/domain) or enable logging on all three of them.

#7) Go to Customize.

#8) Click on Log Dropped Packets.

#9) Select Yes.

#10) Note the file path.

#11) Click OK.

#12) Go to the file path.

#13) Check for port numbers that are blocked.

#14) If the port number you are looking for is not here, that means it is open.

Via Command Line

#1) Right-click on the start menu.

#2) Select Command Prompt (Admin).

#4) Hit Enter.

#5) You will get a list of all blocked and open ports.

#7) If you find nothing, the port is open.

By Using Apps

You can also use apps like CanYouSeeMe or SolarWinds Free Port Scanner to scan the status of your ports. Here I am using CanYouSeeMe.

#1) Go to the website.

#2) Enter your IP address or click on use current IP.

#3) Enter a Port number or select from the drop-down menu on the right side.

#4) Click Check.

You will see which ports are open and which ones are closed.

In Mac

Follow these steps:

#1) Select Applications.

#2) Go to Utilities.

#3) Click on Network Utility.

#4) Select Port Scan.

#5) Type your IP address.

#6) Click on Scan.

You will see the open ports.

In Linux

Here are the steps:

#1) Launch Linux terminal application.

Any of these three commands can tell you which ports are open.

Frequently Asked Questions

Q #1) How do I open ports in Windows 10 firewall?

Answer: From the Control Panel, navigate to System and Security, and click on Windows Firewall. Go to the Advanced settings and right-click on Inbound Rules on the left pane.

Select New Rule, add the port and click Next. Pick the Protocol and the Port Number, click Next again. Select Allow the connection and click on Next. Pick the network type, click Next, name the rule, select Finish.

Q #2) How do I open ports in Windows Firewall 2016?

Answer: From the Start menu, go to Windows Administrative Tools and click on Windows Firewall With Advanced Security. Now click on Inbound Rules, and select New Rule.

Select the Port Radio button and click Next. Select TCP/UDP, specify the port, select either All local ports or specific local ports, enter the port number for a specific port, and click on Next. Select a Profile, click Next, name the rule, click Finish.

Q #3) Does port 445 need to be open?

Answer: TCP 445 is required for file and printer sharing. So, if you need these services, that port will need to be open.

Q #4) Should I open port 139?

Answer: If you are not using a network with NetBios, there is no need for port 139 to be open.

Q #5) How do I know if my port 445 is open?

Answer: Open the Run command and type cmd to open the command prompt. Type: “netstat –na” and hit enter. Find port 445 under the Local Address and check the State. If it says Listening, your port is open.

Conclusion

Usually, you don’t have to worry about ports, your Operating System, network hardware, and application manage them. However, it is always a good idea to keep tools handy in case anything goes wrong and you need to figure out what is causing the issue.

Opening or closing the ports or finding if a port is open or not is not a difficult task. You just have to know the right keys to push.

4 Easy methods for how to check if port is open on Windows

In this how to check if port is open article, we will try to answer all the how-to questions we receive on our website.

We will add a new question from time to time base on new how to questions that users will ask.

For general question, we will try to answer it for the Windows operation system, assuming it can be asking for Windows, Linux, MAC or Mobile device.

Here is a common question regarding how to check a port is open:

To check if a port is open or not on your local computer you will have to use a tool.

Using our own Open Port Viewer tool:

You can download our Open Port Viewer tool and run it (right click and run as administrator).

Open Port Viewer is an easy to use GUI tool to get the current list of used ports on your system.

Open port viewer

Open port viewer

In the list of ports that you will see, please check if you can see the port you are searching.

Using netstat command line tool:

Another option is to use the netstat command line tool.

To do so, please open cmd as administrator:

Open command prompt

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In the command prompt type the following:

example to check for 443 with netstat:

If you see the port number on the left side (red location on the blow image) the port is open.

how to check if port with netstat

how to check if port with netstat

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Read more information about netstat on our netstat command article.

Using telnet command line tool:

Telnet is also a command line tool, to use it you may have to enable it first, on Windows 10.

This is how you enable telnet on windows 10:

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Open the command prompt as administrator (look above how to open cmd as administrator).

Type the following:

example to check for 443 with telnet:

telnet localhost 443

If you get the following error, the port is close:

Connecting To localhost…Could not open a connection to the host, on port 443: Connect failed

Using putty tool:

To check if the port is open using putty tool, you need to download putty from the internet first.

Putty can open a terminal, like telnet or SSH to connect to a remote host, like the telnet command.

We will use it to connect a local port.

Downloading putty from putty website – Putty

When the site is open scroll down to the Alternative binary files section.

Select the 32-bit or 64-bit version of the tool, and download it to your computer.

Once it finishes downloading open it.

Example of using putty to check port 443:

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If you see the following message the port is close:

putty port close

putty port close

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In this article, we show you 4 tools that you can use to check if port is open or not.

The above tools are designed to run on Windows operation system and you might need to be an administrator to use them.

How to Check Open Router Ports: Configure Ports

Have you opened the ports on your router to a server, PC or console and it is not working correctly? Today in this article we are going to explain how to check open ports on your router easily, but first, we have to talk about some fundamental terms to understand why port forwarding (open ports) works or does not work. We will do it in a simple way explaining the difference between a public and private IP, we will talk about NAT, UPnP, DHCP and more.

What is the use of opening the ports of the router?

If you are going to configure a server for something on your local network, where it is necessary for them to access it from the Internet, you need to open ports. For example, for the following uses it is necessary to open ports:

Finally, if you are going to use games on your console, it is recommended to open the DMZ to the consoles, because they usually use many different ports for each game that we are using.

All home routers use NAT to go out to the Internet with multiple devices simultaneously, using the same public IP address. When a computer on the LAN (internal network) tries to access the Internet, NAT is in charge of translating addresses and making use of TCP / UDP ports without having to do anything, it is completely automatic and transparent to the user.

However, if communication starts on the Internet (WAN, external network) to the LAN, it is necessary to open a port to correctly redirect the packets to their destination. As you may have noticed, LAN computers use private addressing that is not routable through the Internet. To make them accessible from the outside, we will have to “open a port” in NAT, so that all the packets that reach the public IP and a specific port are correctly redirected to their recipient.

Before we start explaining how to check open ports on your router, let’s start by explaining the IP classes we have on a home network. To perform a port scan to check the open ports on your router, you have to do it towards a specific type of IP, specifically the public IP that our operator provides us.

Differences between public IP and private IP

Regarding IPs, we could say that there are two classes:

The public IP is the identifier of our network facing the Internet, that is, the one that you have assigned in your home router in the Internet WAN interface. This public IP you cannot put what you want, in this case it is your service provider (operator or ISP) that assigns you one, either statically or dynamically (the latter is the most normal).

In summary, we can say that the devices connected to the same router have different private IP addresses, but the same public IP. In this sense, it is the router that acts as a gateway to communicate with the outside.

How to know the public IP of the Internet connection

Visiting a website that will tell us the public IP

If we want to know what our public IP is, that is, the one that identifies us outside our own network, we can do it through a web easily and quickly. Simply by using a browser in Windows, Android or Linux you can easily find out. We are going to use the web whats-my-ip.net and clicking on the name of the web you will know your public IP address. This is the result that I have obtained from my Windows 10 laptop:

From here, we extract our public IP which is 95.127.152.X. In addition, we have the possibility of geolocating the place where that IP is located and also shows our Internet provider.

Going into the router settings

Another method to know what our public IP address is, is by entering the router directly through its default gateway, in the “Internet status” menu, we can see something like “WAN IP Address”, this IP will be the Public IP that the operator has provided us.

Check open ports on your router

Once we are clear about all the concepts, it is time to check the open ports on your router. To do this, we mainly have two options, the first one and the easiest, is to use a specific website to check that our ports are open. We recommend you access our port test to check it quickly and easily.

Once we have entered, we will simply have to put our public IP address, and put the port or ports that we want to check. This tool allows you to check port ranges and also comma separated ports.

On the other hand, we always have the possibility of Android network apps. One of them is Network Scanner that you can download from Google Play:

In the tools section we have the Port Scanner option. Remember that to do it correctly you have to do it connected via mobile data, and put the public IP that we have in our home, and then indicate the ports to check and click on “Start”.

Then a list will appear with the open ports it has detected.

If it turns out that all ports are closed, even if you have opened them, we recommend checking the following parameters.

Check the private IP configuration of the PC, console or server

These are the results I have gotten from my laptop:

Now we see that our private IP is 192.168.43.79. We can also deduce that the range of our local network is 192.168.43.X and that all the devices are going to be within that range, since we are using a / 24 or 255.255.255.0 subnet mask.

Put fixed private IP so it never changes

Whenever we receive a packet over the Internet, it is destined for our public IP address, and also for a destination port. Thanks to NAT, we will establish communication with our local network of the data that comes to us from the public IP. NAT comes from the English Network Address Translation and is integrated into all the home routers we have today when we use the IPv4 protocol.

If we want to establish contact within the LAN, use the address of the LAN itself, so as not to need to go to the WAN. However, if we want to establish a connection from outside the network and access from the Internet, we will not be able to use these LAN addresses, we need to go through the WAN interface, and to do this, we must go through the NAT of the router «opening the ports ».

Static DHCP

The most recommended method to have a fixed private IP on our devices is to use the Static DHCP feature. The vast majority of routers allow you to assign a private IP address to a specific MAC address, so that the DHCP server always provides you with the same fixed private IP address and that it never changes. Depending on the router, this option is usually in the LAN / DHCP section, and we only have to put the MAC address of our network card, and the IP address that we want.

Put fixed private IP directly on PC, server or console

In IP address we put the IP that we want, to later open the ports. You can find out the subnet mask in the image and the gateway with the ipconfig command that I explained before.

Open the ports on the router correctly

In our router, now we would have to put the fixed private IP address that we have previously configured, and the external (and internal) ports that we want to configure. Normally the external and internal ports are always the same, so just filling in the “external port” option is enough for port forwarding to be successful.

With this we would already have the ports open to our PC. Our router will know where to send the packets and they will not be lost. Once the changes have been applied, you should run the open ports test again to check if they are already open correctly, if they are not, check the firewall of your PC, server or console, since it is possible that you have it closed. If the port test keeps saying that the ports are closed, put a comment and we will help you solve the problem.

An important aspect is that it is very likely that we have the UPnP protocol or also called Universal Plug and Play activated. It is a protocol that allows you to auto-configure the NAT address table to be able to receive files without having to open ports on our router. Programs that support this protocol will open ports automatically and dynamically, but our recommendation for security is that disable this protocol.

We hope that with this guide you can open ports on the router without problems, and check that they are indeed open well.

How to Check If a Port Is Open in Windows 10

You can use a Windows command or third-party utilities

What to Know

This article outlines how to check for open ports in Windows 10, which is necessary if an application cannot access the internet or you want to block an application.

How to Check If a Port Is Open With Netstat

The easiest way to check if a port is open on Windows 10 is by using the Netstat command. ‘Netstat’ is short for network statistics. It will show you what ports each internet protocol (like TCP, FTP, etc.) is currently using.

The command has many parameters, but the ones you’ll need to use to check if a port is open are (a), which provides the active ports, and (b), which will tell you the name of the processes using those ports.

Select the Start menu and type «command.» Right-click on the Command Prompt app and select Run as administrator.

Look for the items on the list with a state of «LISTENING.» These are the processes that are communicating via one of the currently opened ports.

To find the application related to that PID, right-click the task manager and select Task Manager. Select the Details tab. Look in the PID field for the PID you noted from the command prompt screen.

How to Check If a Port Is Working Using Third-Party Apps

If you don’t want to use the command prompt to check for open ports, there are very easy-to-use third-party apps that can help.

TCPView

TCPView is a utility included in Microsoft Sysinternals that shows you a list of all running processes and their associated open ports. This app displays ports opening and closing and packet transfers, all in real-time.

Nirsoft CurrPorts

Nirsoft CurrPorts is another utility to see all ports currently being used by applications and services on your system. Just look for the local ports column to see which of your computer’s ports are active.

The list also includes ports that are being connected to on the remote end (the server out on the internet).

PortQry Command Line Port Scanner

Install PortQry Command Line Port Scanner for another command-line utility dedicated to scanning your computer for open ports. Once you install it, open Command Prompt in administrator mode. PortQry automatically installs in the C:\PortQryV2 directory, so change the directory of your command prompt to that directory.

What Is a Port?

Applications running on your computer reach out and get information and data from servers elsewhere on the internet. These applications and the server know how to communicate based on their IP address and the port number.

Think of the IP address as a street address and the port number as the apartment number. If either the server or application attempts to communicate using any other port number, it won’t work. Every other door will be «locked» because other ports are closed.