How to Partition FAT32 External Hard Drive on Mac

Summary: Creating multiple partitions on FAT32 external hard drive is quite easy on Mac with the help of Disk Utility. However, sometimes, the Disk Utility fails to complete the partitioning operations successfully. In such cases, Stellar Partition Manager can be used to finish the task efficiently.

Among file systems, NTFS is used for Windows devices and HFS for Mac. While a majority of users stick to one of these for a single device / volume / partition, many times, the need to make the same device work on Windows as well as Mac arises. Consider the following scenarios for example:

Suppose you need to work on both Windows and Mac and you need to frequently transfer files between the machines hosting the two Operating Systems. Since you have two separate machines running both operating systems, instead of going a long way and partitioning Mac HDD to install a BootCamp, you resort to working with an external hard drive to transfer files between the two machines. Now when you need to copy data from Windows to the external drive, you need it to run NTFS and when you need to copy data from Mac, you need HFS. However, the external drive can run only one file system at a time. Also, an NTFS drive cannot write to HFS and vice versa. So do you keep reformatting the drive to the desired file system every single time?

The answer to the above problem case is – ‘No’; instead, you work with file formats that can read and write to both Windows and Mac. And such formats include exFAT and FAT32. You can use any one of these formats depending upon the largest file size you need to deal with. FAT32 has a maximum 4GB file size limit whereas exFAT can work with files as large as 16EB (Exabyte, where 1 Exabyte = one billion GBs).

Since FAT32 drives suffice for most file transfer purposes, herein we’re highlighting the technique to format the external drive to FAT32 and then the way to partition that drive on Mac.

Steps to format external hard drive to FAT32 on Mac:

  1. Connect the drive to your Mac
  2. Go to Applications -> Utilities -> Disk Utility
  3. When the Disk Utility opens, select the external drive from the left-hand panel
  4. Click on Erase from the top part of Disk Utility

Note: This will delete all data on the drive so please ensure you have a complete data backup before going ahead with this option.

  1. In the Erase window that appears, assign the name that will be given to the drive and click on Erase. When the process completes, click on Done
  2. Now with the external drive still selected from the left-hand panel, click on Partition from the top menu of Disk Utility
  3. In the Partition window that appears, click next to Format to display a drop-down menu, and select MS-DOS (FAT). This is the format that the drive will be formatted to
  4. Confirm that the name of the drive is correct in the Partition area, and update it if necessary. When ready, click on Apply
  5. Disk Utility will now begin the formatting process. This may take several minutes. Click on Done when the process finishes

Partition FAT32 External Hard Drive

Once you have an external FAT32 hard drive up and running, creating multiple partitions on it is extremely straight-forward. Simply download Stellar Partition Manager and install it on your Mac. Connect the FAT32 external drive to your Mac and launch the software. After that, follow the below-mentioned steps:

  1. Select the external drive in the left-hand panel of the software
  2. Click on Add button from the top menu to create a new partition
  3. In the dialog box that appears, enter a name for the new partition, specify the desired size and the file system you wish the new partition to have
  4. Click on the ‘Tick Mark’ sign to confirm your choices and close the dialog box
  5. Now you’ll be able to see the ‘create new partition’ task queued in the software’s right-hand panel
  6. Select the task and click on Start button from the top menu to start the process
  7. When the task finishes, an appropriate message box will inform you about the same

With Stellar Partition Manager, you can line-up multiple tasks and initiate them in a batch. Also, this software lets you perform a number of partition management operations such as creation, deletion, formatting, resizing, and hiding or revealing Mac partitions.


Using Disk Utility for partitioning and formatting operations is simple and straightforward; however, if you get stuck at any point, avoid taking risks and switch to Stellar Partition Manager for a hassle-free operation. And remember! Never attempt to connect an external drive to multiple computers at the same time as this can quickly damage the drive’s partitions and corrupt the data enclosed in it.