Windows: If you’re testing or benchmarking something like the speed of your hard drive, sometimes you need files of a certain size or format. If you don’t have the desired file on your hard drive, FileFiller can create a dummy in a jiffy.
The no-install portable app asks you to choose a destination for the file, where you can input any file format extension you want. You can choose from three data-fill types: Null, ASCII Character and Random data. Finally, set the file size in bytes, KB, MB or GB. You’ll get your file in no time.
Follow this link:
FileFiller Creates Dummy Files of Custom Size and Format