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How To Check Which Ports Are Open In Windows 10

Geeksdigit Team

May 25, 2026

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Network ports are communication endpoints that allow applications, services, and devices to send and receive data over a network. Every time you browse the internet, use email, play online games, connect to a remote computer, or run server software, specific network ports are used to establish communication. Windows 10 automatically opens and closes ports as needed for various applications and services, but there are situations where you may want to check which ports are currently open on your computer.

Knowing which ports are open can help with troubleshooting network problems, verifying application connectivity, configuring firewalls, diagnosing server issues, improving security, and identifying unwanted network activity. For example, if a web server is not responding, you may need to confirm whether port 80 or port 443 is open. Similarly, if Remote Desktop is not working, checking port 3389 can help determine whether the service is listening for incoming connections.

Windows 10 provides several built-in tools that allow you to view open ports without installing third-party software. You can use Command Prompt, PowerShell, Resource Monitor, Windows Defender Firewall, and advanced networking utilities to identify listening ports and active connections. There are also specialized tools that provide detailed information about which applications are using specific ports.

This guide explains the easiest and most effective ways to check which ports are open in Windows 10.

What Are Open Ports?

An open port is a network port that is actively accepting incoming or outgoing connections.

Common examples include:

• Port 80 – HTTP web traffic
• Port 443 – HTTPS secure web traffic
• Port 21 – FTP
• Port 22 – SSH
• Port 25 – SMTP email
• Port 53 – DNS
• Port 3389 – Remote Desktop Protocol (RDP)

When a service listens on a port, Windows allows network communication through that port according to firewall and application settings.

Method 1: Check Open Ports Using Command Prompt (Netstat)

Netstat is one of the most widely used tools for viewing active network connections and listening ports.

Steps

• Open the Start menu.
• Type Command Prompt.
• Select Run as administrator.
• Enter the following command:

netstat -ano

• Press Enter.
• Review the results.

The output displays:

• Protocol (TCP or UDP)
• Local Address
• Foreign Address
• Connection State
• Process ID (PID)

Ports with a state of LISTENING are actively open and waiting for incoming connections.

For example:

TCP    0.0.0.0:3389    0.0.0.0:0    LISTENING

This indicates that Remote Desktop is listening on port 3389.

Method 2: Display Only Listening Ports

If you only want to view ports currently accepting connections, use a more focused command.

Steps

Open Command Prompt as Administrator and run:

netstat -an | find "LISTENING"

Press Enter.

Windows displays only listening ports, making the list easier to analyze.

This method is particularly useful on systems with many active network connections.

Method 3: Identify Which Application Is Using a Port

Once you find an open port, you may want to know which program is responsible for it.

Step 1: Find the Process ID

Run:

netstat -ano

Locate the port and note its PID.

Example:

TCP    0.0.0.0:8080    0.0.0.0:0    LISTENING    5236

PID = 5236.

Step 2: Identify the Process

Run:

tasklist | find "5236"

Replace 5236 with the actual PID.

The command displays the application using that port.

This helps determine whether the port belongs to a legitimate application or an unexpected process.

Method 4: Check Open Ports Using PowerShell

PowerShell offers modern networking commands with detailed output.

Steps

• Right-click Start.
• Select Windows PowerShell or Terminal.
• Enter:

Get-NetTCPConnection

• Press Enter.

PowerShell displays:

• Local port numbers
• Remote addresses
• Connection state
• Owning process

To display only listening ports:

Get-NetTCPConnection -State Listen

This command shows only ports actively listening for incoming connections.

Method 5: View Open Ports Using Resource Monitor

Resource Monitor provides a graphical interface for viewing network activity.

Steps

• Press Windows + R.
• Type:

resmon

• Press Enter.
• Open the Network tab.
• Expand Listening Ports.

You will see:

• Port numbers
• Protocol type
• Process name
• Process ID

This method is useful for users who prefer graphical tools over command-line utilities.

Method 6: Check Firewall Allowed Ports

Windows Defender Firewall controls which ports can accept incoming connections.

Steps

• Open Start.
• Search for Windows Defender Firewall with Advanced Security.
• Open the application.
• Click Inbound Rules.
• Review configured rules.

You can inspect:

• Port numbers
• Allowed protocols
• Associated applications
• Enabled status

This helps determine whether Windows Firewall permits traffic through a specific port.

Method 7: Use PowerShell to Check a Specific Port

If you only want to verify a particular port, PowerShell provides a simple command.

Steps

Open PowerShell and run:

Test-NetConnection -Port 3389 -ComputerName localhost

Replace 3389 with the desired port number.

The result indicates whether the port is reachable and responding.

This method is commonly used to test services such as:

• Remote Desktop
• Web servers
• Database servers
• FTP services

Method 8: Check Open Ports Using TCPView

TCPView is a free Microsoft utility that displays real-time network activity.

Steps

• Download TCPView from Microsoft’s Sysinternals suite.
• Extract the files.
• Launch TCPView.
• Review active ports and connections.

TCPView displays:

• Process names
• Port numbers
• Protocols
• Connection states
• Remote addresses

Unlike Command Prompt, TCPView updates automatically in real time.

This makes it useful for advanced troubleshooting.

Method 9: Use Netstat With Executable Names

Netstat can directly display executable names associated with open ports.

Steps

Open Command Prompt as Administrator.

Run:

netstat -ab

Press Enter.

The output includes:

• Open ports
• Associated applications
• Executable names

Because Windows examines active processes, this command may take longer to complete than standard Netstat commands.

Method 10: Check Open UDP Ports

Many services use UDP instead of TCP.

Steps

Open Command Prompt.

Run:

netstat -anu

Or:

netstat -an | find "UDP"

Review the output for active UDP ports.

Examples include:

• DNS (Port 53)
• DHCP
• Online gaming services
• Streaming applications

Checking UDP ports can be important when troubleshooting applications that do not rely on TCP connections.

Common Port States Explained

When using Netstat or PowerShell, you may encounter several connection states.

LISTENING

The application is waiting for incoming connections.

ESTABLISHED

An active connection currently exists.

TIME_WAIT

Windows is waiting before fully closing a completed connection.

CLOSE_WAIT

The remote side has closed the connection, but the local process has not yet terminated it.

SYN_SENT

Windows is attempting to establish a connection.

Among these states, LISTENING generally indicates an open port.

How to Check Whether a Port Is Blocked

Using Telnet

Enable Telnet if necessary and run:

telnet localhost 80

Replace the port number as needed.

Using PowerShell

Test-NetConnection localhost -Port 80

A successful connection indicates that the port is open and responding.

Why Check Open Ports?

You may need to inspect open ports for several reasons:

• Troubleshoot application connectivity.
• Verify server configuration.
• Diagnose firewall problems.
• Improve system security.
• Detect unauthorized services.
• Configure network devices.
• Confirm Remote Desktop operation.
• Test web server availability.
• Resolve gaming connection issues.

Regularly reviewing listening ports can help identify unnecessary services and reduce security risks.

Common Problems When Checking Ports

No Listening Ports Displayed

The service may not be running.

Verify that the application is started before checking.

Access Denied Error

Run Command Prompt or PowerShell as Administrator.

Port Not Showing

The application may use a different port than expected.

Consult the application’s documentation.

Firewall Blocking Access

The service may be listening locally while Windows Firewall blocks incoming connections.

Review inbound firewall rules.

Multiple Applications Using Similar Ports

Different applications can use separate ports within the same protocol range.

Check process IDs to identify the correct service.

Frequently Asked Questions

What command shows all open ports in Windows 10?

The most commonly used command is:

netstat -ano

It displays active connections, listening ports, and process IDs.

How do I see which program is using a port?

Use:

netstat -ano

to find the PID, then:

tasklist | find "PID"

to identify the associated application.

What does LISTENING mean?

It means a service or application is actively waiting for incoming network connections on that port.

Is an open port a security risk?

Not necessarily. Many open ports are required for legitimate services. However, unnecessary open ports can increase exposure to unauthorized access attempts.

Can Windows Firewall close open ports?

Yes. Firewall rules can block incoming connections even if an application is listening on a port.

Final Thoughts

Checking which ports are open in Windows 10 is an essential skill for troubleshooting network problems, verifying application functionality, monitoring security, and managing servers or services. Windows includes several built-in tools that make this process straightforward, including Netstat, PowerShell, Resource Monitor, and Windows Defender Firewall. Advanced users can also take advantage of utilities such as TCPView for real-time monitoring and detailed connection analysis.

For most users, the quickest method is opening Command Prompt and running netstat -ano, which provides a complete view of listening ports, active connections, and process IDs. By learning how to identify open ports and the applications using them, you can diagnose connectivity issues more effectively, improve system security, and ensure that network services are operating as expected on your Windows 10 computer.