How do I force a USB drive to FAT32?

The FAT32 file system was introduced in Windows 95 to replace the older FAT16 file system. Compared to modern file systems like NTFS and exFAT, FAT32 is considered outdated, but it still has some advantages. The main reason to format a USB drive to FAT32 is for compatibility – since it’s an older standard, FAT32 is supported by nearly all operating systems, including Windows, macOS, Linux, game consoles, media players, and more. This makes FAT32 useful for external drives that are used to transfer files between different devices. However, there are some downsides – FAT32 only supports individual file sizes up to 4GB and volumes up to 2TB. So for large external drives, a more modern file system like exFAT may be required. Overall, formatting a USB drive to FAT32 trades off support for larger drives and files for wider device compatibility. This guide covers the main methods to force format a drive to FAT32.

Check the File System

Before formatting a USB drive, it’s important to check what file system it’s currently using. This will help determine if you need to reformat it or not.

On Windows, you can check the file system by connecting the USB drive, right-clicking on it in File Explorer, selecting “Properties”, and looking at the “File system” field.

On Mac, open Disk Utility, select the USB drive, and look at the format listed. Common formats on Mac are Mac OS Extended, ExFAT, and FAT32.

On Linux, you can use the lsblk command in the terminal. This will list all connected storage devices along with information like filesystem type.

There are also free third party tools like Partition Wizard that can identify the filesystem of a connected USB drive on Windows, Mac, and Linux.

If the USB is already formatted as FAT32, you won’t need to reformat it. But if it’s using NTFS, HFS+, APFS, or another file system, you’ll want to reformat it to FAT32 before using it.


Back Up Data

Before formatting the USB drive to FAT32, it is crucial to back up any important data already stored on the drive. According to studies, 46% of users experience data loss every year (cite: Formatting a drive will erase all existing data, so backing up first avoids permanent data loss.

There are many potential causes of data loss when reformatting drives, including accidental formatting and filesystem corruption (cite: Making a backup saves copies of important files and provides a way to restore them if needed after formatting.

Back up any personal photos, documents, music, or other data to another storage device or cloud storage before formatting the USB drive. This preparatory step takes a little extra time but provides valuable data protection and peace of mind against permanent data loss.

Using Windows

Windows provides the native Disk Management utility to format drives into FAT32. To use it:

1. Open Disk Management by right-clicking the Start menu and selecting Disk Management.

2. Locate the USB drive in the list of disks and volumes. It may show up as an unknown volume without a drive letter assigned.

3. Right-click on the volume and select “Format”.

4. In the Format window, under File System select “FAT32”. Also check the Quick Format box.

5. Click “Start” to begin formatting the drive.

The Disk Management utility will format the drive and assign a drive letter when complete. The Quick Format option will format the drive faster but does a less thorough job of erasing existing data compared to a standard format.

One limitation of using Windows to format large capacity drives as FAT32 is the 32GB individual file size limit. Windows Disk Management will not allow formatting drives larger than 32GB as FAT32. However third-party tools can format large drives as FAT32 without this limitation.


Using macOS

Mac users can format a USB drive to FAT32 using the built-in Disk Utility app. Here are the steps:

1. Connect the USB drive to your Mac and launch Disk Utility (located in Applications > Utilities).

2. Select the USB drive from the left side pane in Disk Utility.

3. Click Erase at the top. This will open the erase dialogue box.

4. Under Volume Format, select MS-DOS (FAT) from the drop down menu.

5. Under Scheme, select Master Boot Record.

6. Give the USB drive a name.

7. Click Erase. This will format the drive to FAT32.

The process is quick and easy using Disk Utility. One downside is lack of formatting options, but it gets the job done for basic FAT32 formatting (1).


Using Linux

On Linux, the easiest way to format a USB drive to FAT32 is to use the mkfs command in the terminal. The mkfs tool allows you to specify the filesystem type and other formatting options. Here is the basic syntax:

mkfs.fat -F 32 /dev/sdX

Where /dev/sdX is the path to your USB drive. You can find the path by running ‘lsblk’ or ‘df -h’. This will quick format the drive to FAT32.1

For more control over the formatting, you can add flags like -c (cluster size), -l (volume label), -I (volume ID), etc. For example:

mkfs.fat -F 32 -n ‘USBDRIVE’ -I ‘1234-ABCD’ /dev/sdc1

This formats to FAT32, sets the volume label to ‘USBDRIVE’, and the volume ID to ‘1234-ABCD’.

There are also GUI tools like GParted that allow formatting drives from a graphical interface. Overall, the CLI mkfs tool provides the simplest and most direct way to force a USB drive to FAT32 on Linux.

Using Third-Party Tools

While Windows and macOS both provide built-in options for formatting a USB drive as FAT32, many users find third-party tools easier to use with more options and features. Popular third-party USB formatting tools include:

  • Rufus – An open-source utility for Windows that provides a straightforward interface for quickly formatting USB drives. It fully supports FAT32 and offers advanced format options.
  • HP USB Disk Storage Format Tool – A free utility from HP specifically for formatting USB drives. It automatically detects removable drives and has options for FAT32.
  • AOMEI Partition Assistant – This Windows utility allows formatting partitions and drives to FAT32. The free version has limited functionality.

Rufus is one of the most popular third-party USB formatters. It provides both quick formats and full formats to FAT32 with cluster size and volume label options. Rufus is easy to use with an intuitive UI and is trusted by millions of users worldwide.

FAT32 Format Options

When formatting a USB drive to FAT32, there are a few key options to consider:

Cluster size: This refers to the smallest unit that a file system allocates to store data. For FAT32, the default cluster size is 32KB. However, you can specify a different cluster size when formatting the drive. Smaller cluster sizes can help save disk space for smaller files, while larger cluster sizes are more efficient for larger files.

File size limit: One limitation of FAT32 is that it has a maximum file size of 4GB. So if you need to store files larger than 4GB, FAT32 would not be the optimal choice. The file size limit is due to how FAT32 allocates disk space in clusters.

You can tweak the cluster size to optimize for your use case when formatting the drive, but the 4GB file size limitation still remains for FAT32. Some common use cases that work well with 4GB file size limits are storing documents, photos, music, and video files.

Formatting vs Quick Format

When formatting a USB drive, you have the option to do a full format or a quick format. The main differences between these two options are the amount of time the format takes and how thoroughly data is erased.

A full format scans the entire USB drive and overwrites all sectors with zeros to completely erase any existing data. This process can take much longer, sometimes hours depending on the drive size. According to EaseUS, a full format checks the disk for bad sectors, which ensures reliability but adds time.

In contrast, a quick format simply empties the file table and marks all previous sectors as available for new data. It does not actually overwrite existing data on the drive. This allows a quick format to complete much faster, usually within minutes, but it does not fully erase or sanitize a USB drive before reuse. Data remnants may remain on certain sectors and be recoverable with recovery software.

For maximum security when repurposing or reusing a USB drive, a full format is recommended to fully overwrite sensitive data. However, for general everyday use and when in a hurry, a quick format may be sufficient as long as the USB drive contents are non-sensitive.

Verifying the Format

After formatting the USB drive to FAT32, it’s important to verify that the process completed successfully. Here are a few ways to confirm the drive is now using the FAT32 file system:

In Windows, open File Explorer, right-click on the USB drive, select Properties, and check the File System field. It should show “FAT32”.

On a Mac, open Disk Utility, select the USB drive, and check the Format field. It should read “MS-DOS (FAT32)”.

On Linux, open a terminal and run the “lsblk -f” command. Find the USB drive and look at the FSTYPE column. It should say “vfat” which is another name for FAT32.

You can also view the format details by running the “mount” command in Linux or using a third-party utility like Rufus or HDD Scan on any OS. The key is to verify that the USB drive now has a FAT32 file system.

If the format failed for any reason, you may see errors when trying to access the drive or the format type will still show the previous file system like NTFS or exFAT. In that case, you will need to repeat the formatting process until it successfully configures the drive as FAT32.