Create files of specific size in Windows

Export Single File

CMD Command

fsutil file createNew <filename> <length>

Example

fsutil file createNew C:\testfile.txt 1000

Tips:
10K =10 * 1024 = 10240
10M = 10 * 1024 * 1024 = 10485760
100M = 100 * 1024 * 1024 = 10485760

Export Mutiple Files

Create a .bat file

@echo off

set a=0
:loop
fsutil file createnew file%a%.txt 10485760  # size: 10M
echo file%a% done
set /a a+=1
if %a% lss 20 goto :loop  # 20 files

pause