How to create a dummy file in Windows to test network speed and hard drive speed
When you need to know the real speed of your internet connection , or the speed of the storage unit you recently purchased, whether a flash memory, SD Card, or even a new hard drive, you need some empty files to test on.
To make it easier for you, in this article we will show you how to create “dummy” files so you can run such tests and get real results.
Let's say you've purchased a new, fast hard drive for your computer or laptop, and you want to see how fast it is in terms of write and read performance.
Or maybe you've finally upgraded your networking hardware to Gigabit Ethernet or Wireless AC, and want to see how it performs.
Or maybe you want to compare old and new devices to see the difference between the two. The “theoretical” speeds on the packaging won’t really tell you how fast the device you’ve purchased will perform in the real world — so it’s best to test transfer speeds yourself.
To do this, you do not rely on external programs or tools. Rather, you can easily create a dummy file of any size you want and use it to perform the tests, as we will explain below. Note that this method does not require any additional programs, but rather directly through the Windows operating system. It also works in any version of Windows.
All you need to do at first is open the Command Prompt tool and type some simple commands. For that, press Win + R keys together on your keyboard, then in the Run window type “cmd” and press the “OK” button to open the Command Prompt window.
Now you can start creating dummy files of any size. To do this, we will use the " Fsutil " commands which allow you to perform file system operations from the command line. Here is the basic syntax we want to use to create dummy files:
fsutil file createnew filename length
We will replace "filename" with the name and format of the dummy file, and replace "length" with the file size. But there is a point to keep in mind here, which is that the file size must be written in bytes. So if you are not sure how to convert a large file to bytes, here are the values you need to enter to get the sizes you actually want:
1MB = 1048576 bytes
100MB = 104857600 bytes
1GB = 1073741824 bytes
10GB = 10737418240 bytes
100GB = 107374182400 bytes
1TB = 1099511627776 bytes
So, for example, if you wanted to create a dummy file that was a text file and was 1GB in size, the command would be:
fsutil file createnew blankfile.txt 1073741824
Just enter or copy this command into Command Prompt and press Enter key and a dummy file will be created, where you will get the response "File is created" along with the path that contains this file.
Once you have created the dummy file, you can check it on your machine by double-clicking on the This PC icon on your desktop, then going to C partition, then opening the Users folder and then going to the folder with the name of your machine. There you will find the text file called "blankfile" or whatever name you assigned when you ran the command.
By right clicking on the file and selecting “Properties” from the drop down menu, you will be able to see the original size of the file. If you use the above command, you will get a file of exactly 1GB in size as shown in the image above.
Now you can easily create dummy files of any size on your Windows computer, no more searching for programs, tools or files that you don't need on your device to perform tests.
So once you have created a dummy file, you can start using it to test transfer speeds for anything from a portable storage device to your new internal hard drive to your new home network devices. Testing transfer speeds with a dummy file is easy and you get real-world results.
For example, let's say we want to test how long it takes to write a 10GB file to a USB 2 flash drive and then test it on a USB 3 port to see if the port version is a significant factor in the flash drive's performance.
To do this, all we need is a flash drive, a computer with USB 2 and USB 3 ports, and a stopwatch — you can use the one in the Clock app on your phone.
Of course, we'll create a 10GB dummy file because we're more likely to see a difference in transfer rates with a larger file than a smaller one. In other words, with smaller files, the difference will be unnoticeable.
Now insert the flash drive into the USB 2 port (which is black, while the USB 3 port is blue), then transfer the file to the flash drive via the File Explorer tool in Windows, and start the stopwatch.
As you can see in the attached image above, the difference in copying a 10GB file to the flash drive via USB 2 compared to doing the same thing via USB 3 was quite noticeable. On the left is the time taken to transfer the file via USB 2, and on the right is USB 3. The file was transferred via USB 3 in 2 minutes and 20 seconds, while the command via USB 2 took about 4 and a half minutes.
You can certainly repeat this test for any type of transfer you want. Feel free to test how long it takes to transfer a file from one computer on your network to another, or to another hard drive over the Internet (in the cloud), or compare speeds between devices, such as how long it takes to transfer a file to an SSD versus an HDD. There’s no limit to what you can test, so if you’re wondering how your different devices, Internet connection speeds, or network transfers perform, create a dummy file to see what the real result is.