How to Format a USB Drive And Why It’s Necessary

By | March 20, 2022

Formatting a USB drive is easy. Our guide describes the easiest and fastest way to format a USB drive on a Windows computer.

Formatting a USB drive is almost like formatting any other drive. You can use the default settings or you can find out what the various options mean and use the one that best suits your use case. We will help you with the latter, so that you can choose the optimal settings when you format your USB drive.

How to Format a USB Drive In Windows

Whether you’re running Windows XP, Windows 7, Windows 8.1, or Windows 10, the steps are basically the same.

  • Plug in the USB drive.
  • Open Windows File Explorer and go to This PC (aka Computer or My Computer).
  • Right-click the drive, and select Formats…

The formatting options you can customize are File system, Allocation unit size, Volume label and Format options. You can also Restore device defaults if your custom settings don’t work.

To format your drive you just make a choice, click Start, followed by OK to confirm that you really want to erase all data and the drive will be formatted.

However, before you proceed with formatting, you’ll want to understand what each of these options actually mean. So let’s discuss one by one.

Which File System to Choose

In Windows 10, you will see up to four different file systems: NTFS, FAT, FAT32, and exFAT. You won’t see FAT and FAT32 if your drive is larger than 32 GB. So what is the difference between those file systems and which one should you choose? Let’s look at the benefits of each.

NTFS Compared To FAT & FAT32:

  • Read/write files larger than 4 GB and up to maximum partition size
  • Make partition larger than 32 GB
  • Compress files and save disk space
  • Better space management = less fragmentation
  • Allows more clusters on bigger drives = less wasted space
  • Add user permissions to individual files and folders (Windows Professional)
  • On-the-go file encryption using EFS (Encrypting File System; Windows Professional)

FAT & FAT32 Compared To NTFS:

  • Compatible with almost all operating systems
  • Uses less space on the USB drive
  • Fewer disk write operations = faster and less memory usage

ExFAT Compared To FAT & FAT32:

  • Read/write files larger than 4 GB
  • Create a drive partition larger than 32 GB
  • Better space management = less fragmentation

Due to its nature, FAT or better FAT32 is suitable for drives smaller than 32 GB and in environments where you do not need to store files larger than 2 or 4 GB. In other words, a regular sized hard drive (60 GB+) should be formatted with NTFS.

However, due to how NTFS works, it is not recommended for flash drives, even if they are larger than 32 GB. This is where exFAT comes into play. It combines the benefits of FAT (small, fast) and NTFS (large file sizes supported) in a way that is perfect for flash drives.

Keep in mind that FAT and FAT32 are the only cross-platform compatible file systems. NTFS is supported on Linux, but requires hacks or third-party apps to work on Mac. exFAT, on the other hand, is supported on OS X 10.6 (Snow Leopard), but you need a driver to read it on Linux.

If for compatibility or speed reasons you want to use FAT or FAT32, always use FAT32, unless you are using a device of 2 GB or smaller.

Allocation unit size Which one works the most

Hard drives are organized into clusters and the allocation unit size represents the size of a single cluster. The file system records the status of each cluster, i.e. empty or occupied. Once a file or part of a file is written to the cluster, the cluster is occupied, even if there is space left.

Therefore, a larger cluster may result in more wasted or empty space. However, with smaller clusters, the drive becomes slower as each file is broken down into smaller pieces, and it takes longer to pull everything out when the files are accessed.

Therefore, the optimal allocation unit size depends on what you want to do with your USB drive. If you want to store large files on that drive, a large cluster size is better because the drive will be faster. However, if you want to keep small files or run programs from your flash drive, a smaller cluster size will help save space.

Rules of thumb: large drives and/or large files = large allocation unit size (and vice versa)

For a 500 MB USB flash drive, select 512 bytes (FAT32) or 32 kilobytes (FAT). On a 1 TB external hard drive, select 64 kilobytes (NTFS).

What’s that Volume labels

The volume label is the name of the drive. This is optional and you can basically name your drive whatever you want. However, there are some rules to follow, depending on the file system.


  • Maximum 32 characters
  • No tabs
  • Can display uppercase and lowercase characters


  • Maximum 11 characters
  • Missing of the following characters: *? . ,; : / | + = <> []
  • No tabs
  • Will be displayed as all caps
  • You can use spaces, regardless of the file system.

Format Options Which We Recommend

Full format erases file records and scans the drive for bad sectors. The Quick Format option skips scanning, making it much faster. If you’re dealing with a healthy or new drive, if you don’t intend to put important data on it, or if you don’t have the time, choose Quick Format. If not, remove the check mark.

Notes: No option to actually overwrite or delete files; both just delete the drive index file, i.e Mdaisies File Table (MTF). If you want to securely and permanently delete data on your USB drive, formatting won’t work, you’ll have to overwrite the files with a tool like DBAN.