Create large empty files for testing
To create files for quota limit/uploading and testing purposes, open the Terminal – use Spotlight on Mac OS or – Applications > Utilities – type the following command and press Enter:
mkfile -n 19m ~/Desktop/LargeTestFile
This will create a file named “LargeTestFile” on your Desktop with 19 MB. Change the number of the parameter “-n” to create files with different sizes.
Right-click the file on your Desktop and click on “Get Info” to check the size of file or type
du -h filename
to display the size on the Terminal.