# In Windows, using the command line, how do you check if a remote port is open?

## [In Windows, using the command line, how do you check if a remote port is open?](https://serverfault.com/questions/35218/in-windows-using-the-command-line-how-do-you-check-if-a-remote-port-is-open)

[Ask Question](https://serverfault.com/questions/ask)Asked 11 years, 10 months agoActive [3 years, 11 months ago](https://serverfault.com/questions/35218/in-windows-using-the-command-line-how-do-you-check-if-a-remote-port-is-open?lastactivity)Viewed 556k times11638

What is a simple way in Windows to test if traffic gets through to a specific port on a remote machine?[windows](https://serverfault.com/questions/tagged/windows)[networking](https://serverfault.com/questions/tagged/networking)[tcpip](https://serverfault.com/questions/tagged/tcpip)[Share](https://serverfault.com/q/35218)[Improve this question](https://serverfault.com/posts/35218/edit)Follow[edited Dec 9 '14 at 18:57](https://serverfault.com/posts/35218/revisions)[![](https://www.gravatar.com/avatar/49a9e732bedf2a7a022255eceb470e19?s=32\&d=identicon\&r=PG)](https://serverfault.com/users/167332/stan-kurdziel)[Stan Kurdziel](https://serverfault.com/users/167332/stan-kurdziel)10544 bronze badgesasked Jul 2 '09 at 18:01[![](https://www.gravatar.com/avatar/e30f1d60c40c34f9395538cc52930281?s=32\&d=identicon\&r=PG)](https://serverfault.com/users/11384/matt)[Matt](https://serverfault.com/users/11384/matt)1,29344 gold badges1313 silver badges1616 bronze badges

* Related: [superuser.com/questions/11207/…](http://superuser.com/questions/11207/how-can-i-see-all-active-connections) – [Pacerier](https://serverfault.com/users/87017/pacerier) [Feb 23 '15 at 11:00](https://serverfault.com/questions/35218/in-windows-using-the-command-line-how-do-you-check-if-a-remote-port-is-open#comment820093_35218) 

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### 7 Answers

[Active](https://serverfault.com/questions/35218/in-windows-using-the-command-line-how-do-you-check-if-a-remote-port-is-open?answertab=active#tab-top)[Oldest](https://serverfault.com/questions/35218/in-windows-using-the-command-line-how-do-you-check-if-a-remote-port-is-open?answertab=oldest#tab-top)[Votes](https://serverfault.com/questions/35218/in-windows-using-the-command-line-how-do-you-check-if-a-remote-port-is-open?answertab=votes#tab-top)75

I found a hiddem gem the other day from Microsoft that is designed for testing ports:

[Portqry.exe](http://support.microsoft.com/kb/310099)

*"Portqry.exe is a command-line utility that you can use to help troubleshoot TCP/IP connectivity issues. Portqry.exe runs on Windows 2000-based computers, on Windows XP-based computers, and on Windows Server 2003-based computers. The utility reports the port status of TCP and UDP ports on a computer that you select. "*[Share](https://serverfault.com/a/35225)[Improve this answer](https://serverfault.com/posts/35225/edit)Follow[edited Jul 12 '12 at 6:41](https://serverfault.com/posts/35225/revisions)[![](https://www.gravatar.com/avatar/75f5707160697b2164444fc3f5054084?s=32\&d=identicon\&r=PG)](https://serverfault.com/users/68259/steve-bennett)[Steve Bennett](https://serverfault.com/users/68259/steve-bennett)5,1291212 gold badges4040 silver badges5757 bronze badgesanswered Jul 2 '09 at 18:30[![](https://www.gravatar.com/avatar/c04ab8ca94ce77e57e44ecac3b329b38?s=32\&d=identicon\&r=PG\&f=1)](https://serverfault.com/users/12255/peter-m)[Peter M](https://serverfault.com/users/12255/peter-m)93688 silver badges1818 bronze badges

* Note: Attempting to download this from Microsoft returned a page stating the download is "no longer available". – [dgw](https://serverfault.com/users/13440/dgw) [Sep 16 '17 at 0:36](https://serverfault.com/questions/35218/in-windows-using-the-command-line-how-do-you-check-if-a-remote-port-is-open#comment1124982_35225)
* @dgw Thanks for that .. google shows a new version if you search for \`portray" that I'll check out tomorrow – [Peter M](https://serverfault.com/users/12255/peter-m) [Sep 16 '17 at 2:27](https://serverfault.com/questions/35218/in-windows-using-the-command-line-how-do-you-check-if-a-remote-port-is-open#comment1124990_35225)
* 2console version [microsoft.com/downloads/…](http://www.microsoft.com/downloads/details.aspx?familyid=89811747-c74b-4638-a2d5-ac828bdc6983\&displaylang=en) and ui version: [download.microsoft.com/download/3/f/4/…](http://download.microsoft.com/download/3/f/4/3f4c6a54-65f0-4164-bdec-a3411ba24d3a/portqryui.exe) Ref: [support.microsoft.com/en-us/help/310099/…](https://support.microsoft.com/en-us/help/310099/description-of-the-portqry-exe-command-line-utility) – [Junior Mayhé](https://serverfault.com/users/24029/junior-mayh%c3%a9) [Apr 13 '18 at 19:16](https://serverfault.com/questions/35218/in-windows-using-the-command-line-how-do-you-check-if-a-remote-port-is-open#comment1174359_35225) 

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Which version of Windows? For Windows 8/Server 2012 and later, the following works in PowerShell:

```
Test-NetConnection 128.159.1.1 -Port 80
```

Some Googling will also turn up alternatives which use the .NET Framework directly (since PowerShell lets you do that) for systems running lower versions of Windows that won't have `Test-NetConnection` available.

If you're not averse to using third-party utilities, [Nmap](http://nmap.org/) is also a very good friend to have and it works from the command line.[Share](https://serverfault.com/a/637396)[Improve this answer](https://serverfault.com/posts/637396/edit)Follow[edited May 25 '17 at 16:19](https://serverfault.com/posts/637396/revisions)answered Oct 16 '14 at 6:18[![](https://www.gravatar.com/avatar/8f8571493d71202986f2a6ab0dbd7c23?s=32\&d=identicon\&r=PG)](https://serverfault.com/users/54923/iszi)[Iszi](https://serverfault.com/users/54923/iszi)1,76677 gold badges2222 silver badges3333 bronze badges

* 2.Net method: `$connection = (New-Object Net.Sockets.TcpClient).Connect($target,$port); If ($connection.Connected) { $connection.Close() }` – [xXhRQ8sD2L7Z](https://serverfault.com/users/71955/xxhrq8sd2l7z) [Dec 9 '14 at 23:09](https://serverfault.com/questions/35218/in-windows-using-the-command-line-how-do-you-check-if-a-remote-port-is-open#comment789173_637396)
* On Win7, that doesn't work :-( – [Jonesome Reinstate Monica](https://serverfault.com/users/13716/jonesome-reinstate-monica) [Nov 5 '15 at 0:20](https://serverfault.com/questions/35218/in-windows-using-the-command-line-how-do-you-check-if-a-remote-port-is-open#comment915685_637396)
* @samsmith Are you talking about the command in my answer, or the one ST8Z...'s comment? The one in my answer only works for Win8/2k12 and higher, and the answer says as much. – [Iszi](https://serverfault.com/users/54923/iszi) [Nov 5 '15 at 14:38](https://serverfault.com/questions/35218/in-windows-using-the-command-line-how-do-you-check-if-a-remote-port-is-open#comment915918_637396) 
* 1Seems to be Windows 8.1 - Can't seem to find it on Windows 8 – [Andy Krouwel](https://serverfault.com/users/325908/andy-krouwel) [Dec 7 '15 at 10:16](https://serverfault.com/questions/35218/in-windows-using-the-command-line-how-do-you-check-if-a-remote-port-is-open#comment927145_637396)
* 2Works great on Windows 10, and I don't need to install any programs or add any features. Thanks! :) – [Steve Bauman](https://serverfault.com/users/334426/steve-bauman) [Jan 4 '18 at 16:52](https://serverfault.com/questions/35218/in-windows-using-the-command-line-how-do-you-check-if-a-remote-port-is-open#comment1149715_637396)

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Use the telnet command to connect to the server on the specified port, and see if a connection can be established.

**Success:**

```
$ telnet my_server 25
220 my_server ESMTP Postfix
```

**Fail:**

```
$ telnet my_server 23632
Connecting To my_server...Could not open connection to the host, on port 23632:
Connect failed
```

[Share](https://serverfault.com/a/35223)[Improve this answer](https://serverfault.com/posts/35223/edit)Followanswered Jul 2 '09 at 18:05[![](https://www.gravatar.com/avatar/967f06926c0286ce01564d0e772d71c2?s=32\&d=identicon\&r=PG)](https://serverfault.com/users/12695/j%c3%b8rn-schou-rode)[Jørn Schou-Rode](https://serverfault.com/users/12695/j%c3%b8rn-schou-rode)67011 gold badge66 silver badges1212 bronze badges

* 17doesn't work for UDP. – [Adriano Varoli Piazza](https://serverfault.com/users/904/adriano-varoli-piazza) [Jul 2 '09 at 20:23](https://serverfault.com/questions/35218/in-windows-using-the-command-line-how-do-you-check-if-a-remote-port-is-open#comment26601_35223)
* 9UDP is connectionless.. – [Amalgovinus](https://serverfault.com/users/226993/amalgovinus) [Jun 23 '14 at 18:46](https://serverfault.com/questions/35218/in-windows-using-the-command-line-how-do-you-check-if-a-remote-port-is-open#comment722654_35223)

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Telnet will work for TCP.

Netcat is a better tool for these sorts of things, including UDP, watch out though, some AV softwares consider it an 'evil hacker tool'[Share](https://serverfault.com/a/35224)[Improve this answer](https://serverfault.com/posts/35224/edit)Followanswered Jul 2 '09 at 18:07[![](https://i.stack.imgur.com/B3RDi.png?s=32\&g=1)](https://serverfault.com/users/47231/whatsisname)[whatsisname](https://serverfault.com/users/47231/whatsisname)28111 gold badge33 silver badges77 bronze badges[Add a comment](https://serverfault.com/questions/35218/in-windows-using-the-command-line-how-do-you-check-if-a-remote-port-is-open#)1

the following command will list all ports in use on the machine...

```
netstat -a
```

The output contains the protocol, local address, foreign address and current state

[Netstat documentation on microsoft.com](https://www.microsoft.com/resources/documentation/windows/xp/all/proddocs/en-us/netstat.mspx?mfr=true)[Share](https://serverfault.com/a/406744)[Improve this answer](https://serverfault.com/posts/406744/edit)Followanswered Jul 11 '12 at 13:05[![](https://www.gravatar.com/avatar/ec9e61562949e6c0a5251fe3387a070b?s=32\&d=identicon\&r=PG)](https://serverfault.com/users/57439/baldy)[Baldy](https://serverfault.com/users/57439/baldy)18722 silver badges1111 bronze badges

* 13Question asks about open ports on a remote machine, not local. – [Chris S](https://serverfault.com/users/33417/chris-s) [Jun 26 '13 at 13:04](https://serverfault.com/questions/35218/in-windows-using-the-command-line-how-do-you-check-if-a-remote-port-is-open#comment588543_406744)

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Use [**netcat Windows port**](https://eternallybored.org/misc/netcat/):

```
>nc -zvv www.google.com 80
www.google.com [108.177.96.103] 80 (http) open
sent 0, rcvd 0
>

>nc -zvv www.google.com 888
www.google.com [108.177.96.147] 888 (?): TIMEDOUT
sent 0, rcvd 0: NOTSOCK
>
```

[Share](https://serverfault.com/a/811163)[Improve this answer](https://serverfault.com/posts/811163/edit)Followanswered Oct 25 '16 at 12:48[![](https://www.gravatar.com/avatar/e18b024a122df74275dd2c4486e8a2b4?s=32\&d=identicon\&r=PG)](https://serverfault.com/users/62843/rustyx)[rustyx](https://serverfault.com/users/62843/rustyx)1,17722 gold badges1414 silver badges2525 bronze badges[Add a comment](https://serverfault.com/questions/35218/in-windows-using-the-command-line-how-do-you-check-if-a-remote-port-is-open#)-2

'netstat' is you friend.[Share](https://serverfault.com/a/35219)[Improve this answer](https://serverfault.com/posts/35219/edit)Followanswered Jul 2 '09 at 18:03[![](https://www.gravatar.com/avatar/1058fe2c355b79d69928d8ae7b8b9afb?s=32\&d=identicon\&r=PG)](https://serverfault.com/users/22018/quosoo)[quosoo](https://serverfault.com/users/22018/quosoo)10511 bronze badge

* 3Local machine yes, remote machine no. – Joe [Jul 2 '09 at 18:04](https://serverfault.com/questions/35218/in-windows-using-the-command-line-how-do-you-check-if-a-remote-port-is-open#comment26542_35219)
* 3This answer was posted before the edit that specified that it's about a port on remote machine. – quosoo [Jul 2 '09 at 18:11](https://serverfault.com/questions/35218/in-windows-using-the-command-line-how-do-you-check-if-a-remote-port-is-open#comment26543_35219)

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