Quickly create large file on a Windows system

Question

In the same vein as Quickly create a large file on a Linux system, I\'d like to quickly create a large file on a Windows system. By large I\'m thinking 5 GB.

Answer 1

Simple answer in Python: If you need to create a large real text file I just used a simple while loop and was able to create a 5 GB file in about 20 seconds. I know it's crude, but it is fast enough.

outfile = open("outfile.log", "a+")

def write(outfile):
    outfile.write("hello world hello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello worldhello world"+"\n")
    return

i=0
while i < 1000000:
    write(outfile)
    i += 1
outfile.close()

Answer 2

You can use the Sysinternals Contig tool. It has a -n switch which creates a new file of a given size. Unlike fsutil, it doesn't require administrative privileges.

Answer 3

Quick to execute or quick to type on a keyboard? If you use Python on Windows, you can try this:

cmd /k py -3 -c "with open(r'C:\Users\LRiffel\BigFile.bin', 'wb') as file: file.truncate(5 * 1 << 30)"

Answer 4

Another GUI solution : WinHex.

“File” > “New” > “Desired file size” = [X]
“File” > “Save as” = [Name]

Contrary to some of the already proposed solutions, it actually writes the (empty) data on the device.

It also allows to fill the new file with a selectable pattern or random data :

“Edit” > “Fill file” (or “Fill block” if a block is selected)

Answer 5

The simplest way I've found is this free utility: http://www.mynikko.com/dummy/

Creates dummy files of arbitrary size that are either filled with spaces or are filled with non-compressible content (your choice). Here's a screenshot: