TL;DR — Quick Summary

As I was working on setting up an NTP Server for our local network, I wanted to make sure it was set up properly and working.

Note: This article was originally published in 2019. Some steps, commands, or software versions may have changed. Check the current NTP documentation for the latest information.

As I was working on setting up an NTP Server for our local network, I wanted to ensure it was configured correctly and actively responding to client time requests.

To verify time synchronization status without relying on external third-party tools, you can use the built-in Windows Time tool (w32tm) to run a quick test directly from the command line.

Running the w32tm tool with the /stripchart parameter will output a continuous text-based graph showing the time offset between your local computer and the remote NTP server you are querying.

How to use w32tm /stripchart

Open a Command Prompt or PowerShell window and enter the following command:

w32tm /stripchart /computer:time.windows.com

(Note: You can replace time.windows.com with the IP address or hostname of your own internal NTP Server).

Example Output:

C:\>w32tm /stripchart /computer:time.windows.com  
Tracking time.windows.com .  
The current time is 12/16/2019 07:09:47 p. m..  
19:09:47, d:+00.0541615s o:-00.0031265s    
19:09:50, d:+00.0505419s o:-00.0047040s    
19:09:52, d:+00.0538976s o:-00.0029975s    
19:09:54, d:+00.0544312s o:-00.0030872s    
19:09:56, d:+00.0500210s o:-00.0046025s    
19:09:58, d:+00.0541481s o:-00.0030658s    
19:10:00, d:+00.0500892s o:-00.0044170s    
19:10:02, d:+00.0545862s o:-00.0027481s

Understanding the Results

When analyzing the stripchart output:

  • d (delay): This represents the round-trip network delay (in seconds) it took for the request to travel from your client to the server and back.
  • o (offset): This is the actual time difference (in seconds) between your local computer’s clock and the NTP server’s clock. In a healthy synchronization state, this number should be as close to 0 as possible.

Press Ctrl+C to terminate the stripchart test once you have gathered enough data.