Sometimes you just need a large file to test some web forms, APIs, or disk performances.

Usually, you would go to a site to download that file.

But in this post, I’m going to show you how to quickly and easily Generate a Binary file of any size on a Windows machine.

So you don’t have to waste your time.

Let’s get started!

Open the Command Prompt as Administrator.

Run the following command:

fsutil file createnew

For example, this command will create a 1GB file called dummyFileon my Desktop.

fsutil file createnew C:\Users\Carol\Desktop\dummyFile 1073741824

Here is a table with some common file sizes:

Just out of curiosity, if we open the file and inspect its content using Visual Studio Code Hex Editor extension we can see the file is indeed binary and it’s full of 00s.

In human language, that means it’s full of NULL values.

That’s it!

Happy coding

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